These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

Un asteroide proveniente de la Luna  

NASA Astrophysics Data System (ADS)

El descubrimiento de un débil objeto en movimiento por el telescopio Spacewatch (un instrumento dedicado a la búsqueda de Asteroides Cercanos a la Tierra) en 1991, ha generado una gran controversia en la comunidad planetaria. El objeto, denominado 1991 VG, tiene elementos orbitales llamativamente similares a los de la Tierra, lo que ha llevado a B. G. Marsden a aventurar:``El objeto podría ser una nave espacial en retorno (IAUC 5387)". Luego de analizar las características dinámicas de 1991 VG y las diferentes hipótesis sobre su origen, favorecemos la alternativa de que el objeto es un gran fragmento de material eyectado de la Luna durante un reciente impacto (en las últimas decenas de miles de años). El hallazgo en 1983 en la Antártida de meteoritos con composición tipo lunar, confirma la posibilidad de que material de la superficie del satélite puede ser eyectado a velocidades superiores a la de escape del sistema Tierra-Luna y alcance órbitas heliocéntricas. Los elementos orbitales de 1991 VG corresponden a los valores alcanzados por partículas que apenas escapan de la gravedad lunar y entran en órbitas heliocéntricas a través del punto Lagrangiano exterior del sistema Tierra-Sol.

Tancredi, G.

2

CP Violation and K0 decays revelation: study and simulation of neutral Trigger in NA48 experiment -- Violazione di CP e rivelazione dei decadimenti del K0: studio e simulazione del Trigger neutro nell'esperimento NA48  

E-print Network

At the INFN laboratory in Pisa I have prepared my dissertation, which essentially concerned Montecarlo simulation of subnuclear particles decays and investigation of low-noise electronic devices for analyzing high-frequency signals. The team-work was part of NA48/EPSI experiment jointly carried out with European Organization for Nuclear Research CERN, Geneva. ----- Nell'ambito dell'esperimento NA48 in corso al CERN Super Proton Syncrothon (SPS) finalizzato a misurare la violazione diretta di CP in sistemi di particelle K0 attraverso il doppio rapporto R = [N(K_L->Pi0Pi0)]/[N(K_S->Pi0Pi0)] / [N(K_L->Pi+Pi-)]/[N(K_S->Pi+Pi-)] = 1 - 6 Re(e1/e) con una precisione di Re(e1/e) superiore a 2 * 10^-4, il lavoro di tesi si propone di effettuare una simulazione per la rivelazione dei decadimenti neutri dei K0 ed una successiva analisi dei dati raffrontando l'evento fisico generato con metodo Montecarlo e quello ricostruito. Per la misura di e1/e occorre isolare tra i vari modi di decadimento dei K quelli K_S->Pi0Pi0, K...

Calzolari, F

2007-01-01

3

Determinantes del crecimiento de las emisiones de gases de efecto invernadero en España (1990-2007)  

Microsoft Academic Search

La evolución de los gases de efecto invernadero en España se está distanciando notablemente del objetivo marcado por el Protocolo de Kyoto. En el presente trabajo se analizan los diferentes factores que han contribuido al importante aumento experimentado en las emisiones de gases de efecto invernadero provenientes del consumo de energía en España en el período 1990-2007. La metodología de

Vicent Alcantara Escolano; Emilio Padilla Rosa

2009-01-01

4

Futuro de las telecomunicaciones en México ¿Cuál debe ser el rol del gobierno ante los nuevos escenarios del mercado?  

Microsoft Academic Search

El objetivo del presente artículo es analizar las decisiones de política pública que está llevando a cabo el gobierno de México para impulsar la competencia en el mercado de telecomunicaciones. Para ello, se identifica la forma en la que está organizado este sector y se utilizan herramientas provenientes de la teoría económica de redes para evaluar las acciones de este

Fernando G. Toriz Flores

2010-01-01

5

Evaluación económica del uso de las celdas de combustible para generar energía utilizando biogás proveniente de un relleno sanitario  

Microsoft Academic Search

Using an unknown technology in our country and to keep in mind the volume of biogas pro- duced in the landfill of Doña Juana, this work is intended to make an economical evaluation of use fuel cells for energy generation. Once made this evaluation it showed that the project is attractive in a long period of time, but in practical

D. Espinel; E. Giraldo

6

EL VALOR DE LA PRODUCTIVIDAD MARGINAL DEL AGUA EN LA INDUSTRIA MANUFACTURERA COLOMBIANA  

Microsoft Academic Search

Este estudio considera el valor de la productividad marginal del agua en la industria manufacturera colombiana. Su estimación se realiza con información proveniente de aquellos establecimientos industriales que reportaron algún consumo de agua como materia prima, agregados a cuatro dígitos CIIU, en la Encuesta Anual Manufacturera (EAM), durante el periodo 1992 - 1999. A través de la estimación de una

Martha Patricia Cruz; Eduardo Uribe; Harold Coronado

2003-01-01

7

O USO DE MODELOS MATEMÁTICOS NA ESTIMATIVA DA DENSIDADE BÁSICA DA MADEIRA EM PLANTIOS DE CLONES DE Eucalyptus sp  

Microsoft Academic Search

2 , em torno das quais foram cubadas 216 árvores. Foram avaliados 2 clones (híbridos de Eucalyptus grandis e Eucalyptus urophylla), nas idades 3, 4,5 e 6 anos, provenientes de três sítios, na região leste do Brasil, abrangendo a parte leste e nordeste do Estado do Espírito Santo e o extremo sul do Estado da Bahia. Em cada altura de

Cláudio Roberto Thiersch; Jose Roberto Scolforo; Antonio Donizette de Oliveira; Gabriel Dehon; Sampaio Peçanha Rezende; Romualdo Maestri

8

Na+/H+ exchanger regulatory factor 1 overexpression-dependent increase of cytoskeleton organization is fundamental in the rescue of F508del cystic fibrosis transmembrane conductance regulator in human airway CFBE41o- cells.  

PubMed

We have demonstrated that Na(+)/H(+) exchanger regulatory factor 1 (NHERF1) overexpression in CFBE41o- cells induces a significant redistribution of F508del cystic fibrosis transmembrane conductance regulator (CFTR) from the cytoplasm to the apical membrane and rescues CFTR-dependent chloride secretion. Here, we observe that CFBE41o- monolayers displayed substantial disassembly of actin filaments and that overexpression of wild-type (wt) NHERF1 but not NHERF1-Delta Ezrin-Radixin-Moesin (ERM) increased F-actin assembly and organization. Furthermore, the dominant-negative band Four-point one, Ezrin, Radixin, Moesin homology (FERM) domain of ezrin reversed the wt NHERF1 overexpression-induced increase in both F-actin and CFTR-dependent chloride secretion. wt NHERF1 overexpression enhanced the interaction between NHERF1 and both CFTR and ezrin and between ezrin and actin and the overexpression of wt NHERF1, but not NHERF1-DeltaERM, also increased the phosphorylation of ezrin in the apical region of the cell monolayers. Furthermore, wt NHERF1 increased RhoA activity and transfection of constitutively active RhoA in CFBE41o- cells was sufficient to redistribute phospho-ezrin to the membrane fraction and rescue both the F-actin content and the CFTR-dependent chloride efflux. Rho kinase (ROCK) inhibition, in contrast, reversed the wt NHERF1 overexpression-induced increase of membrane phospho-ezrin, F-actin content, and CFTR-dependent secretion. We conclude that NHERF1 overexpression in CFBE41o- rescues CFTR-dependent chloride secretion by forming the multiprotein complex RhoA-ROCK-ezrin-actin that, via actin cytoskeleton reorganization, tethers F508del CFTR to the cytoskeleton stabilizing it on the apical membrane. PMID:19889841

Favia, Maria; Guerra, Lorenzo; Fanelli, Teresa; Cardone, Rosa Angela; Monterisi, Stefania; Di Sole, Francesca; Castellani, Stefano; Chen, Mingmin; Seidler, Ursula; Reshkin, Stephan Joel; Conese, Massimo; Casavola, Valeria

2010-01-01

9

Na+/H+ Exchanger Regulatory Factor 1 Overexpression-dependent Increase of Cytoskeleton Organization Is Fundamental in the Rescue of F508del Cystic Fibrosis Transmembrane Conductance Regulator in Human Airway CFBE41o- Cells  

PubMed Central

We have demonstrated that Na+/H+ exchanger regulatory factor 1 (NHERF1) overexpression in CFBE41o- cells induces a significant redistribution of F508del cystic fibrosis transmembrane conductance regulator (CFTR) from the cytoplasm to the apical membrane and rescues CFTR-dependent chloride secretion. Here, we observe that CFBE41o- monolayers displayed substantial disassembly of actin filaments and that overexpression of wild-type (wt) NHERF1 but not NHERF1-? Ezrin-Radixin-Moesin (ERM) increased F-actin assembly and organization. Furthermore, the dominant-negative band Four-point one, Ezrin, Radixin, Moesin homology (FERM) domain of ezrin reversed the wt NHERF1 overexpression-induced increase in both F-actin and CFTR-dependent chloride secretion. wt NHERF1 overexpression enhanced the interaction between NHERF1 and both CFTR and ezrin and between ezrin and actin and the overexpression of wt NHERF1, but not NHERF1-?ERM, also increased the phosphorylation of ezrin in the apical region of the cell monolayers. Furthermore, wt NHERF1 increased RhoA activity and transfection of constitutively active RhoA in CFBE41o- cells was sufficient to redistribute phospho-ezrin to the membrane fraction and rescue both the F-actin content and the CFTR-dependent chloride efflux. Rho kinase (ROCK) inhibition, in contrast, reversed the wt NHERF1 overexpression-induced increase of membrane phospho-ezrin, F-actin content, and CFTR-dependent secretion. We conclude that NHERF1 overexpression in CFBE41o- rescues CFTR-dependent chloride secretion by forming the multiprotein complex RhoA-ROCK-ezrin-actin that, via actin cytoskeleton reorganization, tethers F508del CFTR to the cytoskeleton stabilizing it on the apical membrane. PMID:19889841

Favia, Maria; Guerra, Lorenzo; Fanelli, Teresa; Cardone, Rosa Angela; Monterisi, Stefania; Di Sole, Francesca; Castellani, Stefano; Chen, Mingmin; Seidler, Ursula; Reshkin, Stephan Joel; Conese, Massimo

2010-01-01

10

Memories of Astronomy Education in Brazil: Clippings from the Discourses of Interviewed Researchers on the Subject. (Spanish Title: Memorias de la Educación en Astronomía en Brasil: Recortes de los Discursos de Investigadores Entrevistados Acerca del Tema ) Memórias da Educação em Astronomia no Brasil: Recortes a Partir das Falas de Pesquisadores Entrevistados sobre o Tema  

NASA Astrophysics Data System (ADS)

This paper presents a historical retrospective concerning data from a research in Astronomy Education in Brazil, after 1973. It was organized on the basis of the speech analysis of national researchers considered references in this field by their peers. Furthermore, it was elaborated on the basis of other studies from the areas of Science Education, Physics and Astronomy. This historical overview was developed in order to facilitate understanding of the contexts in which the interviewed researchers have developed professionally. Moreover, we attempted to recover the memory of the growing field of research in Astronomy Education in the country. We believe that the history presented can help those trying to understand the past in an attempt to resolve current and future demands. Se presenta en este artículo una retrospectiva histórica referente a datos provenientes de la investigación en enseñanza de la astronomía en el Brasil, después de 1973, organizada sobre la base del análisis de los discursos de los investigadores nacionales considerados referencias en este campo, y también en la lectura de las publicaciones en las áreas de Enseñanza de las Ciencias, Física y Astronomía. Este repaso histórico se desarrolló con el fin de facilitar la comprensión de los contextos en los que los investigadores entrevistados se han desarrollado profesionalmente. Por otra parte, se intentó recuperar la memoria del creciente campo de la investigación en Educación en Astronomía en el país. Creemos que el relato presentado puede contribuir a quien trata de comprender el pasado, en un intento de resolver las demandas actuales y futuras. Relata-se neste artigo uma retrospectiva histórica referente a dados provenientes de pesquisa em Educação em Astronomia no país, pós 1973, organizada com base na análise das falas de pesquisadores considerados referências nacionais nesse campo, como também na leitura de publicações das áreas de ensino de Ciências, Física e Astronomia. Tal panorama histórico foi desenvolvido com o intuito de favorecer nossa compreensão sobre os contextos nos quais os pesquisadores entrevistados se desenvolveram profissionalmente. Ademais, buscou-se recobrar a memória do crescente campo de pesquisa em Educação em Astronomia no país. Entendemos que o histórico apresentado possa contribuir para com os que buscam entender o passado na tentativa de solucionar demandas atuais e futuras.

Iachel, Gustavo; Nardi, Roberto

2014-12-01

11

Boletín del Instituto Nacional del Cáncer  

Cancer.gov

La edición electrónica del Boletín del Instituto Nacional del Cáncer se publicó mensualmente desde septiembre de 2009 hasta enero de 2013, con el objetivo de difundir información sobre la investigación del cáncer, tanto de estudios financiados por el NCI y otras dependencias federales, así como de investigaciones realizadas por instituciones en Estados Unidos y alrededor del mundo.

12

Ciclo de vida del VIH Enlace y fusin: El VIH empieza su ciclo de vida  

E-print Network

VIH debe también ligarse a las proteínas CCR5 ó CXCR4 (co- receptores) para entrar en la célula receptor CD4 glucoproteína del VIH envoltura del VIH CCR5 receptor o CXCR4 receptor Un servicio del

Levin, Judith G.

13

Instantánea del cáncer infantil  

Cancer.gov

Información sobre la incidencia y mortalidad del cáncer en los niños, tendencias en el financiamiento del NCI para la investigación del cáncer infantil; así como ejemplos de actividades y adelantos en la investigación relevantes para esta población.

14

Atlas del Genoma del Cáncer: Antecedentes  

Cancer.gov

El Atlas del Genoma del Cáncer es una iniciativa de los Institutos Nacionales de la Salud (NIH) para crear mapas multidimensionales completos de los cambios genómicos clave en los tipos y subtipos principales de cáncer.

15

NaF Documentation  

Cancer.gov

The NaF documentation files are presented in Adobe Acrobat or Word files. PDF Generic Documentation for NaF PDF file Word Generic Documentation for NaFWord file Contact Paula M. Jacobs, Ph.D., 301-435-9181, jacobsp@mail.nih.gov, for information. Print

16

Políticas del sitio web  

Cancer.gov

En el sitio web del NCI se proporcionan enlaces a otros sitios web con fines informativos y para conveniencia del público. Si el usuario selecciona un sitio web externo, saldrá del sitio web del NCI y estará sujeto a las políticas de privacidad y seguridad de dicho sitio.

17

Extensión del Formalismo de Orbitales de Defecto Cuántico al tratamiento del efecto Stark (SQDO).  

NASA Astrophysics Data System (ADS)

El estudio experimental de las interacciones de átomos Rydberg altamente excitados con campos eléctricos ha experimentado un creciente interés durante las dos últimas décadas debido, en gran medida, al desarrollo de nuevas técnicas para crear y estudiar átomos Rydberg en el laboratorio. Acompañando a estas nuevas técnicas experimentales, es necesario el desarrollo de modelos teóricos que nos permitan contrastar sus medidas y conocer mejor los fundamentos de los mismos. Desde el punto de vista teórico el conocimiento del desdoblamiento de los niveles energéticos de un átomo en función de la magnitud del campo eléctrico aplicado (lo que se conoce como mapa Stark) es el mejor punto de partida para la descripción del sistema y un prerrequisito fundamental para el cálculo de distintas propiedades atómicas en presencia del campo eléctrico tales como intensidades de transición, umbrales de ionización de campo eléctrico, tiempos de vida, posición y anchura de cruces evitados, etc. En este trabajo presentamos la adaptación del método de orbitales de defecto cuántico [1,2,3] al tratamiento del efecto Stark (SQDO) [4] y su aplicación al cálculo de los desdoblamientos energéticos y fuerzas de oscilador de estados Rydberg en los átomos de Li, Na y K. El propósito de este estudio es, por un lado, desarrollar métodos fiables para la determinación de propiedades atómicas en presencia de campos eléctricos y, por otro, mostrar la fiabilidad de las funciones de onda QDO en la descripción del efecto Stark en sistemas atómicos.

Menéndez, J. M.; Martín, I.; Velasco, A. M.

18

Omnipresencia del paralelismo Objetivos del proyecto  

E-print Network

-Secundaria Incorporaci´on de contenidos de programaci´on paralela en la rama de tecnolog´ias inform´aticas Facultad;Omnipresencia del paralelismo Objetivos del proyecto Material a desarrollar Programaci´on paralela Para explotar componentes computacionales, para lo que se utiliza la programaci´on paralela. Tipos b´asicos: Dentro de un

Giménez, Domingo

19

Instantánea del cáncer colorrectal  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer colorrectal; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

20

Redes sociales del NCI  

Cancer.gov

Instituto Nacional del CáncerLa página de Facebook cuenta con información de cáncer dirigida al público de habla hispana. Visite nuestra página para leer noticias sobre la investigación del cáncer, conocer los recursos del NCI y publicar sus comentarios y preguntas relacionadas con el cáncer.

21

INTRODUCCION DESCRIPCION DEL PROGRAMA  

E-print Network

INTRODUCCION DESCRIPCION DEL PROGRAMA ADMISION, BECAS E INSTRUMENTOS DE APOYO Programa de Doctorado´atica, U. de Concepci´on, Chile #12;INTRODUCCION DESCRIPCION DEL PROGRAMA ADMISION, BECAS E INSTRUMENTOS DE´on, Chile #12;INTRODUCCION DESCRIPCION DEL PROGRAMA ADMISION, BECAS E INSTRUMENTOS DE APOYO ENTORNO LA

Bürger, Raimund

22

Report from NA49  

E-print Network

The signatures of the onset of deconfinement, found by the NA49 experiment at low SPS energies, are confronted with new results from the Beam Energy Scan (BES) program at BNL RHIC and CERN LHC results. Additionally, new NA49 results on chemical (particle ratio) fluctuations, azimuthal angle fluctuations, intermittency of di-pions, etc. are presented.

Katarzyna Grebieszkow; for the NA49 Collaboration

2011-12-04

23

K measurements with NA48/NA62  

NASA Astrophysics Data System (ADS)

The NA48/2 collaboration has analysed more than one million K±??+?-e±? decays, resulting in the improved determination of branching fraction by a factor of 3 and high precision form factor measurements. Concurrently, about 45000 K±??0?0e±? decays have been analyzed. Background contamination below the percent level and very good ?0 reconstruction allow the first accurate measurement of the branching fraction and decay form factor at the percent level. The achieved precision makes possible the observation of small effects such as ?+?-??0?0 re-scattering. Both K modes decay properties bring new precise inputs to Low Energy QCD studies and can provide strong tests of ChPT predictions. Future prospects include the observation of several thousand decays in similar muonic modes K±??0?0?±? and K±??+?-?±?, that could be studied also in the forthcoming NA62 experiment.

Madigozhin, D.

2013-01-01

24

Acuerdo del Programa del Mal Comportamiento Nombre del Nio: _______________________ Fecha_____________________  

E-print Network

: _______________________ Fecha_____________________ Nombre del padre_______________________ Problemas de la conducta son niño es capaz a esta edad de aprender esta conducta? Sí____ No____ ¿Se portan los otros niños de la misma edad con la conducta deseada? Sí_____ No_____ Si el niño nunca se ha portado con la conducta

25

EVALUACIN DEL IMPACTO AMBIENTAL  

E-print Network

EVALUACIÓN DEL IMPACTO AMBIENTAL Grado en Ciencias Ambientales Universidad de Alcalá Curso DEL IMPACTO AMBIENTAL Código: 670020 Titulación en la que se imparte: Grado en Ciencias Ambientales que se imparte: Español 1. PRESENTACIÓN La evaluación de impacto ambiental de proyectos es un

Espigares, Tíscar

26

MEMORIA DEL DEPARTAMENTO  

E-print Network

ESCUELA UNIVERSITARIA Masó Pareja, Alfredo - 4 - #12;Memoria del Departamento de Fundamentos del Análisis. Mariscal Arlabán, Asier, doctor por la University of Chicago. Martínez Gorricho, Silvia, doctora por la Chicago. Turino, Francesco, doctor por la Universitat Pompeu Fabra. PROFESORES ASOCIADOS Ariza Jiménez

Escolano, Francisco

27

Photoabsorption resonances of Na20, Na21Cl and Na22Cl2 clusters  

NASA Astrophysics Data System (ADS)

Plasma resonance profiles in the visible part of the spectrum were measured by photoabsorption spectroscopy for the clusters Na20, Na21Cl and Na22Cl2 in a beam. The resonance positions in Na20 and Na21Cl are close, suggesting that the Cl- ion does not locate at the center of the metallic droplet and does not strongly modify the effective valence electron density. The spectrum of Na22Cl2 is noticeably dissimilar to the other two, raising the possibility of structural differences and/or incomplete charge transfer.

Xia, C.; Yin, C.; Kresin, V. V.

2009-04-01

28

Hojas informativas del NCI  

Cancer.gov

La colección de hojas informativas del NCI trata de una variedad de temas relacionados con el cáncer. Las hojas informativas se revisan y ponen al día de acuerdo a las investigaciones más recientes sobre el cáncer.

29

Fisiopatología del estreñimiento  

Microsoft Academic Search

ResumenEl estreñimiento es un trastorno extremadamente frecuente en la infancia, responsable de hasta el 25% de todas las consultas gastroenterológicas pediátricas y el 3% de todas las consultas pediátricas ambulatorias. En el 90% de los casos el origen del trastorno es funcional y sólo en un 10% existe un problema orgánico subyacente. Entre las causas orgánicas corrientes del estreñimiento infantil

Peter J. Milla

2007-01-01

30

Il problema del litio.  

NASA Astrophysics Data System (ADS)

Contents: 1. Introduzione. 2. La nucleosintesi del Big Bang. 3. Il litio nelle stelle di popolazione II. 4. I modelli stellari standard. 5. Il litio negli ammassi aperti. 6. Meccanismi di distruzione "non standard". 7. I modelli non-standard applicati alla popolazione II. 8. L'evoluzione Galattica del litio. 9. Quali stelle producono litio? 10. Il litio come elemento chiave per dare un nome agli oggetti stellari più minuscoli. 11. Conclusioni.

D'Antona, F.

1995-03-01

31

Control del cáncer y salud mundial: noticia del Instituto Nacional del Cáncer (NCI)  

Cancer.gov

En combinación con una reunión de alto nivel de las Naciones Unidas sobre enfermedades no transmisibles en países en vías de desarrollo, el doctor Harold Varmus, director del NCI, y el doctor Ted L. Trimble, del NCI, han publicado un comentario en Science Translational Medicine sobre “La integración del control del cáncer en la salud mundial" (Integrating Cancer Control into Global Health).

32

Aceptabilidad del diagnóstico rápido casero para HIV entre hombres gay y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires  

PubMed Central

Resumen El uso del diagnóstico rápido para HIV en Argentina, así como otros países de Latinoamérica, ha sido limitado hasta el momento. Este trabajo reporta los resultados provenientes de un estudio cualitativo realizado entre hombres gays y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires, Argentina. El objetivo principal del mismo fue conocer las ventajas y desventajas que los hombres G&HSH perciben en relación al diagnóstico rápido casero para HIV. Se realizaron ocho grupos focales con 73 participantes en los cuales se discutió acerca de las ventajas y desventajas del uso de los diagnósticos rápidos. Las respuestas fueron codificadas utilizando un programa para análisis de datos cualitativos (NVivo) y analizadas temáticamente. Los participantes describieron numerosas ventajas sobre el uso del diagnóstico rápido casero, aunque algunos reportaron importantes preocupaciones dentro de las cuales se destaca la posibilidad de impulsos suicidas si alguien recibe un resultado positivo estando solo. En términos generales se observó una gran aceptabilidad para el uso del diagnóstico rápido si el mismo es realizado por personal de salud en lugares acondicionados para este fin. PMID:25284951

Balán, Iván C.; Carballo-Diéguez, Alex; Marone, Rubén O.; Pando, María A.; Barreda, Victoria; Ávila, María M.

2011-01-01

33

Aceptabilidad del diagnóstico rápido casero para HIV entre hombres gay y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires.  

PubMed

El uso del diagnóstico rápido para HIV en Argentina, así como otros países de Latinoamérica, ha sido limitado hasta el momento. Este trabajo reporta los resultados provenientes de un estudio cualitativo realizado entre hombres gays y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires, Argentina. El objetivo principal del mismo fue conocer las ventajas y desventajas que los hombres G&HSH perciben en relación al diagnóstico rápido casero para HIV. Se realizaron ocho grupos focales con 73 participantes en los cuales se discutió acerca de las ventajas y desventajas del uso de los diagnósticos rápidos. Las respuestas fueron codificadas utilizando un programa para análisis de datos cualitativos (NVivo) y analizadas temáticamente. Los participantes describieron numerosas ventajas sobre el uso del diagnóstico rápido casero, aunque algunos reportaron importantes preocupaciones dentro de las cuales se destaca la posibilidad de impulsos suicidas si alguien recibe un resultado positivo estando solo. En términos generales se observó una gran aceptabilidad para el uso del diagnóstico rápido si el mismo es realizado por personal de salud en lugares acondicionados para este fin. PMID:25284951

Balán, Iván C; Carballo-Diéguez, Alex; Marone, Rubén O; Pando, María A; Barreda, Victoria; Avila, María M

2011-03-01

34

Estudio del CH interestelar  

NASA Astrophysics Data System (ADS)

El objetivo principal de este proyecto consiste en el estudio de la distribución y abundancia del CH en nubes interestelares a través de la observación de las líneas hiperfinas del CH en 3,3 GHz. El CH es una molécula de amplia distribución en el espacio interestelar y una de las pocas especies que han sido observadas tanto con técnicas de radio como ópticas. Desde el punto de vista tecnológico se ha desarrollado un cabezal de receptor que permitirá la realización de observaciones polarimétricas en la frecuencia de 3,3 GHz, con una temperatura del sistema de 60 K y un ancho de banda de 140 MHz, y que será instalado en el foco primario de la antena parabólica del IAR. El cabezal del receptor es capaz de detectar señales polarizadas, separando las componentes de polarización circular derecha e izquierda. Para tal fin el cabezal consta de dos ramas receptoras que amplificarán la señal y la trasladarán a una frecuencia más baja (frecuencia intermedia), permitiendo de esa forma un mejor transporte de la señal a la sala de control para su posterior procesamiento. El receptor además de tener características polarimétricas, podrá ser usado en el continuo y en la línea, utilizando las ventajas observacionales y de procesamiento de señal que actualmente posee el IAR.

Olano, C.; Lemarchand, G.; Sanz, A. J.; Bava, J. A.

35

DIANA: Anlisis del discurso para la comprensin del conocimiento  

E-print Network

DIANA: Análisis del discurso para la comprensión del conocimiento DIANA: DIscourse ANAlysis by the Spanish Ministry of Economy and Competitiveness. Paolo Rosso coordinates the DIANA project and leads

Rosso, Paolo

36

Pruebas de Papanicolaou y del virus del papiloma humano (VPH)  

Cancer.gov

Hoja informativa que describe los exámenes selectivos de detección del cáncer de cérvix, los cuales incluyen la prueba de Papanicolaou y la prueba de los virus del papiloma humano. La hoja informativa incluye también información acerca de las pautas de exámenes de detección del cáncer de cérvix.

37

Publicacin en Internet de los Datos del Herbario del  

E-print Network

Publicación en Internet de los Datos del Herbario del Departamento de Biología del Recinto-MAPR · Upgrading and Internet publication of the Herbarium of the Department of Biology at the University of Puerto datos a través de la Internet. #12;Georeferenciación · Coordenadas e información obtenidas de la

Gilbes, Fernando

38

Instantánea del sarcoma de Kaposi  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el sarcoma de Kaposi; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

39

Instantánea del cáncer de páncreas  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de páncreas; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

40

Instantánea del cáncer de pulmón  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de pulmón; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

41

Instantánea del cáncer de riñón  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de riñón; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

42

Instantánea del cáncer de tiroides  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de tiroides; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

43

Instantánea del cáncer de próstata  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de próstata; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

44

Instantánea del cáncer de endometrio  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de endometrio; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

45

Instantánea del cáncer de ovario  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de ovario; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

46

Instantánea del cáncer de vejiga  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de vejiga; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

47

Instantánea del cáncer de estómago  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de estómago; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

48

Instantánea del cáncer de esófago  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de esófago; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

49

Grupos financieros al servicio del rey de Espaa Fines del siglo XVII -principios del XVIII  

E-print Network

Grupos financieros al servicio del rey de España Fines del siglo XVII - principios del XVIII Existe, en un primer momento, bajo el ángulo casi exclusivo de los servicios financieros al Estado2 . La financieros, arrendamientos de impuestos, derechos señoriales o ingresos privados, suministro de víveres, de

Paris-Sud XI, Université de

50

BREAKFAST MENU (665 MG NA)  

E-print Network

), Cranberry(7.5 MG), Orange (5 MG), Prune(10 MG), V-8(85 MG) LOW SODIUM (2000 GM NA) ACCOMPANIMENTS: Fresh/Lowfat Italian/Lowfat French) (5 MG) DESSERTS: Angel Food Cake (280 MG) Diet Gelatin (5 MG) Diet Pudding: Vanilla SODIUM (2000 GM NA) COLD ENTREES: Chicken Caesar Salad (440 MG) (Oil & Vinegar/Lowfat Italian

Oliver, Douglas L.

51

Nevado del Huila, Columbia  

NASA Technical Reports Server (NTRS)

Nevado del Huila Volcano in Colombia is actually a volcanic chain running north to south, capped by a glacier. With peaks ranging in height from 2,600 to 5,780 meters (8,530 to 18,960 feet), Nevado del Huila is a stratovolcano composed of alternating layers of hardened lava, solidified ash, and volcanic rocks. Its first recorded eruption occurred in the mid-sixteenth century. The long-dormant volcano erupted again in mid-April 2007. A few months before the eruption, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite captured this image of Nevado del Huila, on February 23, 2007. In this image, the bright white area just east of the central summit is ice. Immediately west of the summit are bare rocks, appearing as blue-gray. West of those rocks, white reappears, but this patch of white results from clouds hovering in the nearby valley. In the east, the colors turn to brown (indicating bare rock) and bright green (indicating vegetation). ASTER photographed Nevado del Huila near the end of a long phase of quietude. On April 17, 2007, local authorities recorded seismic activity associated with rock fracturing on the volcano's central summit, according to the ReliefWeb Website. Activity intensified the following day with an eruption and mudflows, forcing thousands of nearby residents to evacuate. As the Associated Press reported, the eruption caused avalanches and floods that wiped away both houses and bridges. It marked the volcano's first recorded eruption since the Spanish colonized the area five centuries earlier. NASA image created by Jesse Allen, using data provided courtesy of the NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team.

2007-01-01

52

PAX/hr. PAX/mi. $/Pass. Green Route (Old) n/a n/a n/a  

E-print Network

.0 (out of 6) n/a n/a Safety Committee Road Tests 4 5 11 4 15 Passing 4 4 9 3 14 Clinics Conducted 2 2 7 4 1 Charter MPH n/a n/a 10.35 14.76 13.28 Charter Cost/Hour n/a n/a $22.25 $24.80 $25.48 Customer

Acton, Scott

53

Temas y rumbos del teatro rural hispanoamericano del siglo XX.  

E-print Network

Argentina. Digno de encomio, pues, el esfuerzo de Buenaventura y Gene por continuar la tradición del teatro folklórico.3 En lo que atañe a las creencias y al temperamento del campesino criollo, los autores hispanoamericanos han dado en la escena un... hijo del patrón que abusó de la inocencia de su prometida. Sabe que el encuentro podría ser funesto. El hombre de campo es también supersticioso. A veces mezcla las creencias de orden supersticioso con las religiosas. La presencia de ciertas aves...

Neglia, Erminio G.

1971-10-01

54

Pesquisas Baseadas na Localizao e na Orientao em Dispositivos Mveis  

E-print Network

Pesquisas Baseadas na Localização e na Orientação em Dispositivos Móveis Hugo Aguiar, Maria Beatriz Carmo, Paulo Pombinho, Ana Paula Afonso Departamento de Informática, Faculdade de Ciências, Universidade.di.fc.ul.pt,apa@di.fc.ul.pt Sumário A crescente utilização de dispositivos móveis e a sua evolução, com o surgimento de modelos

Carmo, Maria Beatriz

55

Challenges for Na-ion Negative Electrodes  

E-print Network

Na-ion batteries have been proposed as candidates for replacing Li-ion batteries. In this paper we examine the viability of Na-ion negative electrode materials based on Na alloys or hard carbons in terms of volumetric ...

Chevrier, V. L.

56

Intermitência alfvênica gerada por caos na atmosfera solar e no vento solar  

NASA Astrophysics Data System (ADS)

Dados medidos no vento solar rápido proveniente dos buracos coronais revelam que os plasmas no meio interplanetário são dominados por flutuações Alfvênicas, caracterizadas por uma alta correlação entre as variações do campo magnético e da velocidade do plasma. As flutuações exibem muitas características esperadas em turbulência magneto-hidrodinâmica totalmente desenvolvida, tais como intermitência e espectros contínuos. Contudo, os mecanismos responsáveis pela evolução de turbulência Alfvênica intermitente não são completamente compreendidos. Neste trabalho a teoria de caos é usada para explicar como sistemas Alfvênicos, modelados pela equação Schrödinger não-linear derivativa e pela equação Kuramoto-Sivashinsky, podem se tornar fortemente caóticos à medida em que parâmetros do plasma são variados. Pequenas perturbações no parâmetro de dissipação podem fazer com que o sistema mude bruscamente de um regime periódico, ou fracamente caótico, para um regime fortemente caótico. As séries temporais das flutuações do campo magnético nos regimes fortemente caóticos exibem comportamento intermitente, em que fases laminares ou fracamente caóticas são interrompidas por fortes estouros caóticos. É mostrado que o regime fortemente caótico é atingido quando as soluções periódicas ou fracamente caóticas globalmente estáveis interagem com soluções do sistema que são fortemente caóticas, mas globalmente instáveis. Estas soluções globalmente instáveis são conjuntos caóticos não-atrativos conhecidos como selas caóticas, e são responsáveis pelos fortes estouros nos regimes intermitentes. Selas caóticas têm sido detectadas experimentalmente em uma grande variedade de sistemas, sendo provável que elas desempenhem um papel importante na turbulência intermitente observada em plasmas espaciais.

Rempel, E. L.; Chian, A. C.-L.; Macau, E. E. N.; Rosa, R. R.

2003-08-01

57

Acerca del Centro para la Salud Mundial del NCI  

Cancer.gov

El Centro para la Salud Mundial (CGH) coordina y fija las prioridades en las actividades que lleva a cabo el Instituto Nacional del Cáncer a nivel mundial. Su objetivo es avanzar la investigación mundial del cáncer y reducir las muertes causadas por esta enfermedad.

58

Competitividad del sector del vidrio templado en Colombia  

Microsoft Academic Search

La industria nacional del vidrio templado es un sector en crecimiento, que necesita desarrollar ventajas competitivas como la innovación en sus procesos y productos a través de tecnología dura y blanda, y desplegar una logística integrada que permita la articulación de la cadena de valor y la orientación al cliente. Las empresas del sector vienen desarrollando, de acuerdo con su

Javier Mauricio Mendoza Paredes

2008-01-01

59

Bioinformática: Perspectivas na Medicina Bioinformática: Perspectivas na Medicina Bioinformática: Perspectivas na Medicina Bioinformática: Perspectivas na Medicina Bioinformática: Perspectivas na Medicina Bioinformatics: Perspectives in Medicine  

Microsoft Academic Search

A medicina moderna requer a integração e análise de grandes quantidades de dados genômicos, moleculares, celulares, associados a informações clínicas, desta forma apresentando desafios fenomenais para a Bioinformática. Esta área interdisciplinar da ciência, que começou com a análise de seqüências gênicas e cresceu na direção do desenvolvimento de técnicas automatizadas de anotação de genomas e transcriptomas, está agora caminhando na

Glaucius Oliva

2008-01-01

60

Vacunas contra los virus del papiloma humano  

Cancer.gov

Hoja informativa acerca de las vacunas contra los virus del papiloma humano (VPH) para prevenir infecciones con ciertos tipos de VPH, los cuales son la causa principal del cáncer de cuello del útero o cérvix.

61

Formation Enthalpies of NaK Alloys.  

NASA Astrophysics Data System (ADS)

We have made accurate pseudopotential calculations of the total energy of Na, K, NaK in the CsCl structure, and Na_2K in the MgZn2 structure. For Na_2K, the only ordered alloy known to exist, we obtained a formation enthalpy H=-18 meV/atom whereas for NaK we obtained H=+7.5 meV/atom. It is argued that the negative H of Na_2K is a consequence of triangular bonds between some of the Na atoms.

Kleinman, Leonard; Zhu, Ming J.; Bylander, D. M.

1996-03-01

62

DIPARTIMENTO DI MEDICf NA MOLECOLART  

E-print Network

esigenze oggettive a supporto della richiesta; si rende noto che il Dipartimento di Medicina Molecolare SILVESTRI COM PETENZE DEL PRESTATORE: - Laurea in Fisica e Chimica e Tecnologia Farmaceutica - competenza in spettroscopia nell'infra rosso DURATA E LUOGO Dl ESECUZIONE: 5 mesi - Dipartimento di Medicina Molecolare

Guidoni, Leonardo

63

The Na-K-Cl Cotransporters  

Microsoft Academic Search

The Na-K-Cl cotransporters are a class of membrane proteins that transport Na, K, and Cl ions into and out of a wide variety of epithelial and nonepithelial cells. The transport process mediated by Na-K-Cl cotransporters is characterized by electroneutrality (almost always with stoichiometry of 1Na:1K:2Cl) and inhibition by the “loop” diuretics bumetanide, benzmetanide, and furosemide. Presently, two distinct Na-K-Cl cotransporter

Mark Haas; Bliss Forbush

1998-01-01

64

Seminrio de Socializao: Estgio na  

E-print Network

Socialização da disciplina de Estágio Supervisionado na Educação Infantil, Curso de Pedagogia/UFSC (2013Seminário de Socialização: Estágio na Educação Infantil 09 de Dezembro 14h - Abertura do Seminário Infantil, Anos Iniciais e estudantes das 6ª e 7ª fases. 15h30m - Encerramento do Seminário. Mesa "Relações

Floeter, Sergio Ricardo

65

modelado y analisis del transporte del herbicida glifosato  

E-print Network

(2) Departamento de Ingeniería del Terreno, Universidad Politécnica de Cataluña (España). (3) Department of ... tools for the study of water and contaminant transport in the unsaturated zone. ..... Dynamics of Fluids in Porous Media. Esevier ...

2001-03-12

66

Original Contribution Involvement of Na+  

E-print Network

Original Contribution Involvement of Na+ /K+ -ATPase in hydrogen peroxide-induced hypertrophy production of reactive oxygen species (ROS) was required for ouabain-induced hypertrophy in cultured cardiac alone is sufficient to induce hypertrophy. A moderate amount of H2O2 was continuously generated

Brand, Paul H.

67

Europlanet NA2 Science Networking  

NASA Astrophysics Data System (ADS)

Europlanet RI / NA2 Science Networking [1] focused on determining the major goals of current and future European planetary science, relating them to the Research Infrastructure that the Europlanet RI project [2] developed, and placing them in a more global context. NA2 also enhanced the ability of European planetary scientists to participate on the global scene with their own agenda-setting projects and ideas. The Networking Activity NA2 included five working groups, aimed at identifying key science issues and producing reference books on major science themes that will bridge the gap between the results of present and past missions and the scientific preparation of the future ones. Within the Europlanet RI project (2009-2012) the NA2 and NA2-WGs organized thematic workshops, an expert exchange program and training groups to improve the scientific impact of this Infrastructure. The principal tasks addressed by NA2 were: • Science activities in support to the optimal use of data from past and present space missions, involving the broad planetary science community beyond the "space club" • Science activities in support to the preparation of future planetary missions: Earth-based preparatory observations, laboratory studies, R&D on advanced instrumentation and exploration technologies for the future, theory and modeling etc. • Develop scientific activities, joint publications, dedicated meetings, tools and services, education activities, engaging the public and industries • Update science themes and addressing the two main scientific objectives • Prepare and support workshops of the International Space Science Institute (ISSI) in Bern and • Support Trans National Activities (TNAs), Joined Research Activities (JRAs) and the Integrated and Distributed Information Service (IDIS) of the Europlanet project These tasks were achieved by WG workshops organized by the NA2 working groups, by ISSI workshops and by an Expert Exchange Program. There were 17 official WG workshops and in addition there were numerous smaller NA2 WG meetings during the conferences (EPSC, EGU, etc.) and other events. The total number of NA2 meetings and workshops was 37. There were three NA2 supported ISSI workshops within the Europlanet project. The first ISSI workshop "Comparison of the plasma-spheres of Mars, Venus, and Titan" organized by K. Szego was held in December 2009. The second workshop "Quantifying the Martian Geochemical Reservoirs" by M. Toplis was held in April 2011. The third one, themed "Giant Planet Magnetodiscs and Aurorae" by N. Krupp, N. Achilleos and C. Arridge, was in November 2012. All three ISSI workshops were selected by the ISSI scientific committee to be organized within the frame of ISSI/Europlanet agreement and held in Bern. The main objective of the Expert Exchange Program was to support the activities of Europlanet RI with experts whenever needed. The programme provided funding for short visits (up to one week) of expert with the goal of improving infrastructure facilities and services offered to the scientific community by the Europlanet RI participant (contractor) laboratories or institutes. Between July 2009 and September 2012 26 applications were selected. Acknowledgement: Europlanet RI was funded by the European Commission under the 7th Framework Program, grant 228319 "Capacities Specific Programme" - Research Infrastructures Action. References: [1] http://www.europlanet-ri.eu/ [2] https://europlanet-scinet.fi/

Harri, Ari-Matti; Szego, Karoly; Genzer, Maria; Schmidt, Walter; Krupp, Norbert; Lammer, Helmut; Kallio, Esa; Haukka, Harri

2013-04-01

68

Ionic regulation of Na absorption in proximal colon: cation inhibition of electroneutral Na absorption  

SciTech Connect

Active Na absorption (J/sub net//sup NA/) in rabbit proximal colon in vitro is paradoxically stimulated as (Na) in the bathing media is lowered with constant osmolarity. J/sub m..-->..s//sup Na/ increases almost linearly from 0 to 50 mM (Na)/sub 0/ but then plateaus and actually decreases from 50 to 140 mM (Na)/sub 0/, consistent with inhibition of an active transport process. Both lithium and Na are equally effective inhibitors of J/sub net//sup Na/, whereas choline and mannitol do not block the high rate of J/sub net//sup Na/ observed in decreased (Na)/sub 0/. Either gluconate or proprionate replacement of Cl inhibits J/sub net//sup Na/. J/sub net//sup Na/ at lowered (Na)/sub 0/ is electrically silent and is accompanied by increased Cl absorption; it is inhibited by 10/sup -3/ M amiloride and 10/sup -3/ theophylline but not by 10/sup -4/ M bumetanide. Epinephrine is equally effective at stimulating Na absorption at 50 and 140 mM (Na). Na gradient experiments are consistent with a predominantly serosal effect of the decreased (Na)/sub 0/. These results suggest that 1) Na absorption in rabbit proximal colon in vitro is stimulated by decreased (Na); 2) the effect is cation specific, both Na and Li blocking the stimulatory effect; 3) the transport is mediated by Na-H exchange and is Cl dependent but 4) is under different regulatory mechanisms than the epinephrine-sensitive Na-Cl cotransport previously described in proximal colon. Under the appropriate conditions, proximal colon absorbs Na extremely efficiently. Na-H exchange in this epithelium is cation inhibitable, either directly or by a secondary regulatory process.

Sellin, J.H.; De Soignie, R.

1987-01-01

69

Harold Varmus investido bajo juramento como 14.º director del Instituto Nacional del Cáncer  

Cancer.gov

Ganador del Premio Nobel, doctor Harold E. Varmus, prestó juramento hoy como 14.º director del Instituto Nacional del Cáncer (NCI).  "Es muy estimulante que estés de regreso con nosotros", dijo la secretaria del Departamento de Salud y Servicios Humanos Kathleen Sebelius en la ceremonia de toma de juramento. “Hoy se abre un nuevo capítulo para el Instituto Nacional del Cáncer”.

70

Antioxidantes y prevención del cáncer  

Cancer.gov

Hoja informativa acerca de los antioxidantes, sustancias que pueden proteger las células del daño causado por moléculas inestables conocidas como radicales libres. El daño de los radicales libres puede resultar en cáncer.

71

NOTICIAS DEL 24/Julio/08  

E-print Network

de la materia oculta del Universo "Estamos mirando a los cielos, y usando los instrumentos más instrumentos más grandes para ayudarnos a predecir qué sucederá con las cosas más pequeñas", dijo David Toback

Toback, David

72

Case Study: del Amo Bioventing  

EPA Science Inventory

The attached presentation discusses the fundamentals of bioventing in the vadose zone. The basics of bioventing are presented. The experience to date with the del Amo Superfund Site is presented as a case study....

73

NA49 and NA61/SHINE experiments: results and perspectives  

E-print Network

The Super Proton Synchrotron (SPS) covers one of the most interesting regions of the QCD phase diagram $(T - \\mu_B)$. On the one hand there are indications that the energy threshold for deconfinement is reached already at low SPS energies. On the other hand theoretical calculations locate the QCD critical end-point at energies accessible at the SPS. In this paper the NA49 signatures of the onset of deconfinement are presented. Results are shown on pion production, the kaon to pion ratio, slopes of transverse mass spectra ("temperature"), and event-by-event particle ratio fluctuations versus collision energy, for central $Pb+Pb$ interactions. Next we show possible indications of the critical point in event-by-event mean transverse momentum and multiplicity fluctuations. Finally we discuss the future ion program of the NA61/SHINE experiment (energy scan with light ions).

Katarzyna Grebieszkow

2010-05-04

74

Alberto del Pozo  

NSDL National Science Digital Library

The Cuban Heritage Collection of the University of Miami Libraries was a recipient of 17 original illustrations by Alberto del Pozo in 1998 from the Campilli family. "The Oricha Collection" is their gift, and it contains illustrations in pen, crayon, and ink and the collection "pays homage to the primary gods and goddesses that comprise the Afro-Cuban religion of Santer'a." The "Introduction" near the top of the page, is a good place for visitors to start learning about Pozo, who was a Parson's School of Design-trained, Cuban artist who died at the age of 47. The "Biographical Sketch" is worth looking at as well. Examples of his colorful, heavily patterned and symbolism-intensive drawings of Santeria gods and goddesses can be found in the link "Gallery". The description of each drawing is given in English and Spanish. Finally, visitors interested in more information on the Santeria, can look at the "Further Readings" link for authoritative books on the subject.

75

PARAULES DEL RECTOR EN L'ACTE DE CELEBRACI DEL NADAL DEL 2008  

E-print Network

és el quart any que m'apropo a aquest faristol per desitjar-vos Bon Nadal i el millor per al proper aniversari de la Declaració Universal dels Drets Humans de les Nacions Unides. La declaració ­us en recomano, tot allò que causa la misèria dels humans: les guerres, la pobresa extrema, la crueltat. Uns versos de

Verschure, Paul

76

Inauguracin del "Frum del Mediterrneo" Alicante, 24 de marzo de 2004  

E-print Network

recordar a las víctimas del terror del 11 de marzo, a sus familiares y amigos, y en ellas a todas las nuestros malos sueños y presagios. Como negar que para muchos de nosotros, la percepción del islam por

Escolano, Francisco

77

Dirio Econmico -Universidades A Repblica na Academia  

E-print Network

Diário Económico - Universidades A República na Academia Autor: Carla Castro Id: 1067471 Data #12;Diário Económico - Universidades A República na Academia Autor: Carla Castro Id: 1067465 Data.503,19 EUR #12;Diário Económico - Universidades A República na Academia Autor: Carla Castro Id: 1067468 Data

Instituto de Sistemas e Robotica

78

Regulation of Na+ channels by luminal Na+ in rat cortical collecting tubule  

PubMed Central

The idea that luminal Na+ can regulate epithelial Na+ channels was tested in the cortical collecting tubule of the rat using whole-cell and single-channel recordings. Here we report results consistent with the idea of Na+ self-inhibition.Macroscopic amiloride-sensitive currents (INa) were measured by conventional whole-cell clamp. INa was a saturable function of external Na+ concentration ([Na+]o) with an apparent Km of 9 mm. Single channel currents (iNa) were measured in cell-attached patches. iNa increased with pipette Na+ concentration with an apparent Km of 48 mm. Since INa= (iNa)NPo, the different Km values imply that the channel density (N) and/or open probability (Po) increase as [Na+]o decreases. Reduction of [Na+]o after increasing intracellular Na+ concentration also increased the outward amiloride-sensitive conductance, consistent with activation of the Na+ channels.The underlying mechanism was studied by changing pipette Na+ concentration while recording from cell-attached patches. No increase in NPo was observed, suggesting that the effect is not a direct interaction between [Na+]o and the channel.[Na+]o was varied outside the patch-clamp pipette while recording from cell-attached patches. When amiloride was in the bath to prevent Na+ entry, no change in NPo was observed.Activation of the channels by hyperpolarization was observed with 140 mm Na+o but not with 14 mm Nao +.The results are consistent with the concept of self-inhibition of Na+ channels by luminal Na+. Activation of the channels by lowering [Na+]o is not additive with that achieved by hyperpolarization. PMID:9547389

Palmer, Lawrence G; Sackin, Henry; Frindt, Gustavo

1998-01-01

79

ROINN NA CEILTIS IS NA GIDHLIG / CELTIC AND GAELIC POSTGRADUATE STUDY IN 2014-15  

E-print Network

Brosnachaidh na Gàidhlig / Gaelic Language Promotion Trust ­ Margaret Callan, Urras Brosnachaidh na Gàidhlig, cROINN NA CEILTIS IS NA GÀIDHLIG / CELTIC AND GAELIC POSTGRADUATE STUDY IN 2014-15 Taught degree (which can be written in English or Gaelic) Research degrees · MRes (see separate sheet) One-year degree

Glasgow, University of

80

Características del viento en estrellas Be derivadas del perfil H?  

NASA Astrophysics Data System (ADS)

El estudio teórico de perfiles H? y su variabilidad en estrellas Be ha sido frecuentemente desarrollado en base a modelos de envolturas circunestelares inhomogéneas, donde la geometría del material es responsable de la forma del perfil dependiendo de la dirección de observación. Nosotros damos una interpretación alternativa y proponemos que la mayoría de las propiedades de esta línea tienen origen en la base de un viento estelar y de una estructura cromosférica anexa a la fotósfera. Encontramos que típicos perfiles H? en Be, como son los llamados pole-on y winebottle, pueden ser reproducidos cualitativamente sin recurrir a la existencia de una envoltura asimétrica. Analizamos como la línea H? permite identificar la posible estructura del viento en la región donde éste se inicia.

Rohrmann, R.; Cidale, L.

81

El libro del Relogio del Palacio de las Horas  

NASA Astrophysics Data System (ADS)

This paper resume the investigation entitled ``El libro del Relogio del Palacio de las Horas''. That consist in an edition of the original text of the book of the Clock of the Palace of the Hours from the Books of the knowledge of Astronomy of Alfonso X (Manuscript 156, Complutense University). And a description of the astronomical functionality of the Clock of the Palace of the Hours. It includes a geometric description of the positional astronomy on which the operation of the Palace is based.

Morales, J. D.

2009-08-01

82

EL ROL DEL GNERO DENTRO DEL PROCESO DE APRENDIZAJE COLABORATIVO  

E-print Network

de sexo y la forma en que esto afecta las actividades colaborativas. En el presente trabajo se describen los resultados de un experimento desarrollado con el fin de establecer que la diferencia de sexo]. Varios estudios también han demostrado que las diferencias de sexo en el uso del computador están

Guerrero, Luis

83

El papel del estado en la construcción del desarrollo sostenible: el caso del turismo en el Caribe Insular  

Microsoft Academic Search

La discusión acerca de la pertinencia de la intervención estatal en el mercado ha sido reiterativa en la historia del pensamiento económico. El turismo es otro ejemplo de que la regulación es no sólo necesaria sino fundamental, para corregir las asimetrías de un mercado que está lejos de cumplir los supuestos que motivaron la teoría del interés individual y del

Johannie James Cruz

2009-01-01

84

Redetermination of NaGdS2, NaLuS2 and NaYS2.  

PubMed

The title structures NaGdS2 (sodium gadolinium sulfide), NaLuS2 (sodium lutetium sulfide) and NaYS2 (sodium yttrium sulfide) were redetermined in order to improve the structural information available for the family of group 1 and thallium rare earth sulfides, which are isostructural with the rhombohedral ?-NaFeO2 structure type. In particular, the present investigation has been directed at the rhombohedral sodium rare earth sulfides. The observed dependence of the fractional coordinate z(S(2-)) on the identity of the rare earth element in the newly determined structures is in agreement with the known structures of the potassium and rubidium analogues. Crystals of NaGdS2 and NaLuS2 display obverse-reverse twinning. PMID:24898952

Fábry, Jan; Havlák, Lubomír; Ku?eráková, Monika; Dušek, Michal

2014-06-01

85

Aggiornamento del Piano Forestale Regionale: obiettivi e  

E-print Network

31-01-2013 1 Aggiornamento del Piano Forestale Regionale: obiettivi e azioni da condividere Davide green economy 2. Settore forestale: una green economy o una grey economy? 3. La struttura del Piano 4

Pettenella, Davide

86

UNIVERSIDAD SIMON BOLIVAR SEDE DEL LITORAL  

E-print Network

UNIVERSIDAD SIMON BOLIVAR SEDE DEL LITORAL ESPECIALIZACIÓN EN TELECOMUNICACIONES DECANATO DE comportamiento de las empresas del sector de las Telecomunicaciones considerando aspectos tecnológicos, políticos comunicación. Las organizaciones y su entorno. 2.- Entorno económico de las telecomunicaciones. Nociones

Vásquez, Carlos

87

Instantánea del cáncer de cuello uterino  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de cuello uterino; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

88

Instantánea del cáncer de seno (mama)  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de seno (mama); así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

89

The effect of Na vapor on the Na content of chondrules  

NASA Technical Reports Server (NTRS)

Chondrules contain higher concentrations of volatiles (Na) than expected for melt droplets in the solar nebula. Recent studies have proposed that chondrules may have formed under non-canonical nebular conditions such as in particle/gas-rich clumps. Such chondrule formation areas may have contained significant Na vapor. To test the hypothesis of whether a Na-rich vapor would minimize Na volatilization reaction rates in a chondrule analog and maintain the Na value of the melt, experiments were designed where a Na-rich vapor could be maintained around the sample. A starting material with a melting point lower that typical chondrules was required to keep the logistics of working with Na volatilization from NaCl within the realm of feasibility. The Knippa basalt, a MgO-rich alkali olivine basalt with a melting temperature of 1325 +/- 5 C and a Na2O content of 3.05 wt%, was used as the chondrule analog. Experiments were conducted in a 1 atm, gas-mixing furnace with the fO2 controlled by a CO/CO2 gas mixture and fixed at the I-W buffer curve. To determine the extent of Na loss from the sample, initial experiments were conducted at high temperatures (1300 C - 1350 C) for duration of up to 72 h without a Na-rich vapor present. Almost all (up to 98%) Na was volatilized in runs of 72 h. Subsequent trials were conducted at 1330 C for 16 h in the presence of a Na-rich vapor, supplied by a NaCl-filled crucible placed in the bottom of the furnace. Succeeding Knudsen cell weight-loss mass-spectrometry analysis of NaCl determined the P(sub Na) for these experimental conditions to be in the 10(exp -6) atm range. This value is considered high for nebula conditions but is still plausible for non-canonical environments. In these trials the Na2O content of the glass was maintained or in some cases increased; Na2O values ranged from 2.62% wt to 4.37% wt. The Na content of chondrules may be controlled by the Na vapor pressure in the chondrule formation region. Most heating events capable of producing chondrules are sufficient to volatile Na. Sodium volatilization reaction rates will be reduced to varying degrees from melt droplets, depending on the magnitude of the P(sub Na) generated. A combination of Na vapor during, and Na diffusion back into chondrules after, formation could maintain and/or enrich Na concentrations in chondrules.

Lewis, R. Dean; Lofgren, Gary E.; Franzen, Hugo F.; Windom, Kenneth E.

1993-01-01

90

Arquitectura del Sistema de Gestin del ancho de Banda y Proteccin (SGBP) para entornos de redes  

E-print Network

Arquitectura del Sistema de Gestión del ancho de Banda y Protección (SGBP) para entornos de redes}@eia.udg.es Resumen. En el presente artículo se describe la arquitectura de un sistema inte- gral de gestión del ancho 4 detalla la arquitectura propuesta del sistema. Por último, se presentan las conclusiones y futuros

Ortega, Eusebi Calle

91

Elementos estratégicos para afianzar y mejorar la competitividad del Valle del Cauca  

Microsoft Academic Search

El estudio de competitividad del departamento del Valle del Cauca aborda el análisis simultáneo de los factores competitivos que integran el desarrollo económico regional; desempeño de los sectores productivos, la inserción internacional del sector industrial, la infraestructura, el capital humano y social, el avance tecnológico, el medioambiente, y los recursos institucionales. El examen de los factores competitivos y su contraste

Manuel Guillermo Bonilla; Juan Carlos Ramírez J

2005-01-01

92

Las ganancias del comercio y el intercambio desigual en los modelos del comercio internacional  

Microsoft Academic Search

Se examina el problema del intercambio desigual de trabajo entre países desarrollados y en desarrollo y su vinculación con las condiciones del comercio de beneficio mutuo. Para ello se utilizan los principales modelos teóricos del comercio internacional basado en las ventajas comparativas, y se amplía al caso de dos factores el concepto de relación de intercambio de trabajo derivada del

Francisco Martínez Soler; Andrei Martínez Finkelshtein

2005-01-01

93

The process of GaN single crystal growth by the Na flux method with Na vapor  

Microsoft Academic Search

Ga melts were heated in a boron nitride crucible at 800°C and 5MPa of N2 for 8–200h with Na vapor. Colorless and transparent prismatic GaN single crystals grew from a Na–Ga melt which was formed by dissolution of Na from the gas phase. Nitrogen was probably introduced into the melt with Na. The time dependence of the Na fraction (rNa=Na\\/(Na+Ga))

Takahiro Yamada; Hisanori Yamane; Hirokazu Iwata; Seiji Sarayama

2006-01-01

94

Growth of binary organic NLO crystals: m.NA-p.NA and m.NA-CNA system  

NASA Technical Reports Server (NTRS)

Experiments were carried out to grow 3.Nitroaniline (m.NA) crystals doped with 4.Nitroaniline (p.NA) and 2.chloro 4.Nitroaniline (CNA). The measured undercooling for m.NA, p.NA, and CNA were 0.21 tm K, 0.23 tm K, and 0.35 tm K respectively, where tm represents the melting temperature of the pure component. Because of the crystals' large heat of fusion and large undercooling, it was not possible to grow good quality crystals with low thermal gradients. In the conventional two-zone Bridgman furnace we had to raise the temperature of the hot zone above the decomposition temperature of CNA, p.NA, and m.NA to achieve the desired thermal gradient. To avoid decomposition, we used an unconventional Bridgman furnace. Two immiscible liquids, silicone oil and ethylene glycol, were used to build a special two-zone Bridgman furnace. A temperature gradient of 18 K/cm was achieved without exceeding the decomposition temperature of the crystal. The binary crystals, m.NA-p.NA and m.NA-CNA, were grown in centimeter size in this furnace. X-ray and optical characterization showed good optical quality.

Singh, N. B.; Henningsen, T.; Hopkins, R. H.; Mazelsky, R.

1993-01-01

95

EVOLUZIONE-WEB -1 -Evoluzione del Web  

E-print Network

EVOLUZIONE-WEB - 1 - Evoluzione del Web (fonte prof. Polillo) #12;- 2 - L'evoluzione del web EVOLUZIONE-WEB · Dal primo sito Web (1991) il Web è in continua crescita, e in continua evoluzione tecnologia, il mercato, i comportamenti delle persone · Le fasi della storia del Web: Web 1.0, Web 2.0, il

De Antonellis, Valeria

96

La teoría General del Empleo  

Microsoft Academic Search

I. Comentarios sobre las cuatro discusiones en la edición anterior de puntos de la Teoría General, 209. - II. Ciertos puntos definitivos en los que el autor difiere con teorías anteriores, 212. – La teoría del interés expuesta de nuevo, 215. – Incertidumbres y fluctuaciones de la inversión, 217. – III. Demanda y oferta para la producción total, 219. –

John Maynard Keynes

2007-01-01

97

Deliquescence of NaCl–NaNO3, KNO3–NaNO3, and NaCl–KNO3 salt mixtures from 90 to 120°C  

PubMed Central

We conducted reversed deliquescence experiments in saturated NaCl–NaNO3–H2O, KNO3–NaNO3–H2O, and NaCl–KNO3–H2O systems from 90 to 120°C as a function of relative humidity and solution composition. NaCl, NaNO3, and KNO3 represent members of dust salt assemblages that are likely to deliquesce and form concentrated brines on high-level radioactive waste package surfaces in a repository environment at Yucca Mountain, NV. Discrepancy between model prediction and experiment can be as high as 8% for relative humidity and 50% for dissolved ion concentration. The discrepancy is attributed primarily to the use of 25°C models for Cl–NO3 and K–NO3 ion interactions in the current Yucca Mountain Project high-temperature Pitzer model to describe the nonideal behavior of these highly concentrated solutions.

Carroll, Susan; Craig, Laura; Wolery, Thomas J

2005-01-01

98

The effect of NA vapor on the NA content of chondrules  

NASA Astrophysics Data System (ADS)

Chondrules contain higher concentrations of volatiles (Na) than expected for melt droplets in the solar nebula. Recent studies have proposed that chondrules may have formed under non-canonical nebular conditions such as in particle/gas-rich clumps. Such chondrule formation areas may have contained significant Na vapor. To test the hypothesis of whether a Na-rich vapor would minimize Na volatilization reaction rates in a chondrule analog and maintain the Na value of the melt, experiments were designed where a Na-rich vapor could be maintained around the sample. A starting material with a melting point lower that typical chondrules was required to keep the logistics of working with Na volatilization from NaCl within the realm of feasibility. The Knippa basalt, a MgO-rich alkali olivine basalt with a melting temperature of 1325 +/- 5 C and a Na2O content of 3.05 wt%, was used as the chondrule analog. Experiments were conducted in a 1 atm, gas-mixing furnace with the fO2 controlled by a CO/CO2 gas mixture and fixed at the I-W buffer curve. To determine the extent of Na loss from the sample, initial experiments were conducted at high temperatures (1300 C - 1350 C) for duration of up to 72 h without a Na-rich vapor present. Almost all (up to 98%) Na was volatilized in runs of 72 h. Subsequent trials were conducted at 1330 C for 16 h in the presence of a Na-rich vapor, supplied by a NaCl-filled crucible placed in the bottom of the furnace. Succeeding Knudsen cell weight-loss mass-spectrometry analysis of NaCl determined the PNa for these experimental conditions to be in the 10-6 atm range. This value is considered high for nebula conditions but is still plausible for non-canonical environments. In these trials the Na2O content of the glass was maintained or in some cases increased; Na2O values ranged from 2.62% wt to 4.37% wt. The Na content of chondrules may be controlled by the Na vapor pressure in the chondrule formation region. Most heating events capable of producing chondrules are sufficient to volatile Na. Sodium volatilization reaction rates will be reduced to varying degrees from melt droplets, depending on the magnitude of the PNa generated. A combination of Na vapor during, and Na diffusion back into chondrules after, formation could maintain and/or enrich Na concentrations in chondrules.

Lewis, R. Dean; Lofgren, Gary E.; Franzen, Hugo F.; Windom, Kenneth E.

1993-12-01

99

NA-NET numerical analysis net  

SciTech Connect

This report describes a facility called NA-NET created to allow numerical analysts (na) an easy method of communicating with one another. The main advantage of the NA-NET is uniformity of addressing. All mail is addressed to the Internet host ``na-net.ornl.gov`` at Oak Ridge National Laboratory. Hence, members of the NA-NET do not need to remember complicated addresses or even where a member is currently located. As long as moving members change their e-mail address in the NA-NET everything works smoothly. The NA-NET system is currently located at Oak Ridge National Laboratory. It is running on the same machine that serves netlib. Netlib is a separate facility that distributes mathematical software via electronic mail. For more information on netlib consult, or send the one-line message ``send index`` to netlib{at}ornl.gov. The following report describes the current NA-NET system from both a user`s perspective and from an implementation perspective. Currently, there are over 2100 members in the NA-NET. An average of 110 mail messages pass through this facility daily.

Dongarra, J. [Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science]|[Oak Ridge National Lab., TN (United States); Rosener, B. [Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science

1991-12-01

100

NA-NET numerical analysis net  

SciTech Connect

This report describes a facility called NA-NET created to allow numerical analysts (na) an easy method of communicating with one another. The main advantage of the NA-NET is uniformity of addressing. All mail is addressed to the Internet host na-net.ornl.gov'' at Oak Ridge National Laboratory. Hence, members of the NA-NET do not need to remember complicated addresses or even where a member is currently located. As long as moving members change their e-mail address in the NA-NET everything works smoothly. The NA-NET system is currently located at Oak Ridge National Laboratory. It is running on the same machine that serves netlib. Netlib is a separate facility that distributes mathematical software via electronic mail. For more information on netlib consult, or send the one-line message send index'' to netlib{at}ornl.gov. The following report describes the current NA-NET system from both a user's perspective and from an implementation perspective. Currently, there are over 2100 members in the NA-NET. An average of 110 mail messages pass through this facility daily.

Dongarra, J. (Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science Oak Ridge National Lab., TN (United States)); Rosener, B. (Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science)

1991-12-01

101

Painful Na-channelopathies: an expanding universe.  

PubMed

The universe of painful Na-channelopathies--human disorders caused by mutations in voltage-gated sodium channels--has recently expanded in three dimensions. We now know that mutations of sodium channels cause not only rare genetic 'model disorders' such as inherited erythromelalgia and channelopathy-associated insensitivity to pain but also common painful neuropathies. We have learned that mutations of NaV1.8, as well as mutations of NaV1.7, can cause painful Na-channelopathies. Moreover, recent studies combining atomic level structural models and pharmacogenomics suggest that the goal of genomically guided pain therapy may not be unrealistic. PMID:23664154

Waxman, Stephen G

2013-07-01

102

The NA62 RICH Detector  

NASA Astrophysics Data System (ADS)

The NA62 experiment is designed to measure the very rare kaon dacay K^+ rightarrow ?^+ ?bar? at the CERN SPS with a 10% accuracy. The Standard Model prediction for the branching ratio is (8.5 ± 07) × 10-11. One of the challenging aspect of the experiment is the suppression of the K+ ? ?+v? background at the 10-12 level. To satisfy this requirement a Ring Imaging Cherenkov Detector (RICH), able to separate pions from muons in the momentum range between 15 and 35 GeV/c, with a muon rejection factor better than 10-2, is needed. The RICH must also have a time resolution of about 100 ps to disentangle accidental time associations of beam particles with pions. The RICH will have a very long focal length (17 m) and will be filled with Ne gas at atmospheric pressure.

Cassese, A.

2014-06-01

103

NA62 Low Mass Spectrometer  

NASA Astrophysics Data System (ADS)

The NA62 experiment at CERN aims at a precision measurement of the ultra-rare decay K^+ rightarrow ?^+?bar?. A low mass (˜ 1.8%X0) spectrometer, whose construction is ongoing, has been designed to track charged kaon decays products. The system operates in vacuum, and will be operative in October 2014, when the first physics run is scheduled. The straw detector is made of 4 stations, each equipped with 1792 straws, arranged in 4 views (X, Y, U and V). A high aperture magnet (MNP33), placed between the second and the third chamber, provides a 0.36T dipole vertical B-field, required to measure the momentum of the charged particles. A 64-straws prototype was constructed in 2010. It was used as test bench for electronics commissioning and detector characterization. Time resolution and space-time relation were measured. A first test with a full chamber and final beam setup was performed in November 2012.

Palladino, V.

2014-06-01

104

Na(+) /Ca(2+) exchange and Na(+) /K(+) -ATPase in the heart.  

PubMed

This paper is the third in a series of reviews published in this issue resulting from the University of California Davis Cardiovascular Symposium 2014: Systems approach to understanding cardiac excitation-contraction coupling and arrhythmias: Na(+) channel and Na(+) transport. The goal of the symposium was to bring together experts in the field to discuss points of consensus and controversy on the topic of sodium in the heart. The present review focuses on cardiac Na(+) /Ca(2+) exchange (NCX) and Na(+) /K(+) -ATPase (NKA). While the relevance of Ca(2+) homeostasis in cardiac function has been extensively investigated, the role of Na(+) regulation in shaping heart function is often overlooked. Small changes in the cytoplasmic Na(+) content have multiple effects on the heart by influencing intracellular Ca(2+) and pH levels thereby modulating heart contractility. Therefore it is essential for heart cells to maintain Na(+) homeostasis. Among the proteins that accomplish this task are the Na(+) /Ca(2+) exchanger (NCX) and the Na(+) /K(+) pump (NKA). By transporting three Na(+) ions into the cytoplasm in exchange for one Ca(2+) moved out, NCX is one of the main Na(+) influx mechanisms in cardiomyocytes. Acting in the opposite direction, NKA moves Na(+) ions from the cytoplasm to the extracellular space against their gradient by utilizing the energy released from ATP hydrolysis. A fine balance between these two processes controls the net amount of intracellular Na(+) and aberrations in either of these two systems can have a large impact on cardiac contractility. Due to the relevant role of these two proteins in Na(+) homeostasis, the emphasis of this review is on recent developments regarding the cardiac Na(+) /Ca(2+) exchanger (NCX1) and Na(+) /K(+) pump and the controversies that still persist in the field. PMID:25772291

Shattock, Michael J; Ottolia, Michela; Bers, Donald M; Blaustein, Mordecai P; Boguslavskyi, Andrii; Bossuyt, Julie; Bridge, John H B; Chen-Izu, Ye; Clancy, Colleen E; Edwards, Andrew; Goldhaber, Joshua; Kaplan, Jack; Lingrel, Jerry B; Pavlovic, Davor; Philipson, Kenneth; Sipido, Karin R; Xie, Zi-Jian

2015-03-15

105

U Gorskome kotaru kao na Strawberry Hillu  

E-print Network

:// don-wolf.artistwebsites.com/. Trenutno radi na knjizi o djetinjstvu na Strawberry Hillu i iskustvima u Hrvatskoj s naslo- vom “Nazvala me je gospodin Wolf”. Q Don s jednom od svojih omiljenih fotografija: “Hrvatska ?asna sestra hodaju?i po kiši...

Boley, Colleen; Stakun, Rebecca; Novak, Charles; Pirnat-Greenberg, Marta

2012-07-01

106

Regulation of Na+ fluxes in plants  

PubMed Central

When exposed to salt, every plant takes up Na+ from the environment. Once in the symplast, Na+ is distributed within cells and between different tissues and organs. There it can help to lower the cellular water potential but also exert potentially toxic effects. Control of Na+ fluxes is therefore crucial and indeed, research shows that the divergence between salt tolerant and salt sensitive plants is not due to a variation in transporter types but rather originates in the control of uptake and internal Na+ fluxes. A number of regulatory mechanisms has been identified based on signaling of Ca2+, cyclic nucleotides, reactive oxygen species, hormones, or on transcriptional and post translational changes of gene and protein expression. This review will give an overview of intra- and intercellular movement of Na+ in plants and will summarize our current ideas of how these fluxes are controlled and regulated in the early stages of salt stress. PMID:25278946

Maathuis, Frans J. M.; Ahmad, Izhar; Patishtan, Juan

2014-01-01

107

Long range intermolecular interactions between the alkali diatomics Na2, K2, and NaK  

NASA Astrophysics Data System (ADS)

Long range interactions between the ground state alkali diatomics Na2-Na2, K2-K2, Na2-K2, and NaK-NaK are examined. Interaction energies are first determined from ab initio calculations at the coupled-cluster with singles, doubles, and perturbative triples [CCSD(T)] level of theory, including counterpoise corrections. Long range energies calculated from diatomic molecular properties (polarizabilities and dipole and quadrupole moments) are then compared with the ab initio energies. A simple asymptotic model potential ELR=Eelec+Edisp+Eind is shown to accurately represent the intermolecular interactions for these systems at long range.

Zemke, Warren T.; Byrd, Jason N.; Michels, H. Harvey; Montgomery, John A.; Stwalley, William C.

2010-06-01

108

Long range intermolecular interactions between the alkali diatomics Na(2), K(2), and NaK.  

PubMed

Long range interactions between the ground state alkali diatomics Na(2)-Na(2), K(2)-K(2), Na(2)-K(2), and NaK-NaK are examined. Interaction energies are first determined from ab initio calculations at the coupled-cluster with singles, doubles, and perturbative triples [CCSD(T)] level of theory, including counterpoise corrections. Long range energies calculated from diatomic molecular properties (polarizabilities and dipole and quadrupole moments) are then compared with the ab initio energies. A simple asymptotic model potential E(LR)=E(elec)+E(disp)+E(ind) is shown to accurately represent the intermolecular interactions for these systems at long range. PMID:20590191

Zemke, Warren T; Byrd, Jason N; Michels, H Harvey; Montgomery, John A; Stwalley, William C

2010-06-28

109

Nedd4 mediates control of an epithelial Na+ channel in salivary duct cells by cytosolic Na+  

PubMed Central

Epithelial Na+ channels are expressed widely in absorptive epithelia such as the renal collecting duct and the colon and play a critical role in fluid and electrolyte homeostasis. Recent studies have shown that these channels interact via PY motifs in the C terminals of their ?, ?, and ? subunits with the WW domains of the ubiquitin-protein ligase Nedd4. Mutation or deletion of these PY motifs (as occurs, for example, in the heritable form of hypertension known as Liddle’s syndrome) leads to increased Na+ channel activity. Thus, binding of Nedd4 by the PY motifs would appear to be part of a physiological control system for down-regulation of Na+ channel activity. The nature of this control system is, however, unknown. In the present paper, we show that Nedd4 mediates the ubiquitin-dependent down-regulation of Na+ channel activity in response to increased intracellular Na+. We further show that Nedd4 operates downstream of Go in this feedback pathway. We find, however, that Nedd4 is not involved in the feedback control of Na+ channels by intracellular anions. Finally, we show that Nedd4 has no influence on Na+ channel activity when the Na+ and anion feedback systems are inactive. We conclude that Nedd4 normally mediates feedback control of epithelial Na+ channels by intracellular Na+, and we suggest that the increased Na+ channel activity observed in Liddle’s syndrome is attributable to the loss of this regulatory feedback system. PMID:9618557

Dinudom, A.; Harvey, K. F.; Komwatana, P.; Young, J. A.; Kumar, S.; Cook, D. I.

1998-01-01

110

Cytosolic Na+ Controls an Epithelial Na+ Channel Via the Go Guanine Nucleotide-Binding Regulatory Protein  

NASA Astrophysics Data System (ADS)

In tight Na+-absorbing epithelial cells, the rate of Na+ entry through amiloride-sensitive apical membrane Na+ channels is matched to basolateral Na+ extrusion so that cell Na+ concentration and volume remain steady. Control of this process by regulation of apical Na+ channels has been attributed to changes in cytosolic Ca2+ concentration or pH, secondary to changes in cytosolic Na+ concentration, although cytosolic Cl- seems also to be involved. Using mouse mandibular gland duct cells, we now demonstrate that increasing cytosolic Na+ concentration inhibits apical Na+ channels independent of changes in cytosolic Ca2+, pH, or Cl-, and the effect is blocked by GDP-? -S, pertussis toxin, and antibodies against the ? -subunits of guanine nucleotide-binding regulatory proteins (Go). In contrast, the inhibitory effect of cytosolic anions is blocked by antibodies to inhibitory guanine nucleotide-binding regulatory proteins (Gi1/Gi2. It thus appears that apical Na+ channels are regulated by Go and Gi proteins, the activities of which are controlled, respectively, by cytosolic Na+ and Cl-.

Komwatana, P.; Dinudom, A.; Young, J. A.; Cook, D. I.

1996-07-01

111

Extracellular Na+ levels regulate formation and activity of the NaX/alpha1-Na+/K+-ATPase complex in neuronal cells  

PubMed Central

MnPO neurons play a critical role in hydromineral homeostasis regulation by acting as sensors of extracellular sodium concentration ([Na+]out). The mechanism underlying Na+-sensing involves Na+-flow through the NaX channel, directly regulated by the Na+/K+-ATPase ?1-isoform which controls Na+-influx by modulating channel permeability. Together, these two partners form a complex involved in the regulation of intracellular sodium ([Na+]in). Here we aim to determine whether environmental changes in Na+ could actively modulate the NaX/Na+/K+-ATPase complex activity. We investigated the complex activity using patch-clamp recordings from rat MnPO neurons and Neuro2a cells. When the rats were fed with a high-salt-diet, or the [Na+] in the culture medium was increased, the activity of the complex was up-regulated. In contrast, drop in environmental [Na+] decreased the activity of the complex. Interestingly under hypernatremic condition, the colocalization rate and protein level of both partners were up-regulated. Under hyponatremic condition, only NaX protein expression was increased and the level of NaX/Na+/K+-ATPase remained unaltered. This unbalance between NaX and Na+/K+-ATPase pump proportion would induce a bigger portion of Na+/K+-ATPase-control-free NaX channel. Thus, we suggest that hypernatremic environment increases NaX/Na+/K+-ATPase ?1-isoform activity by increasing the number of both partners and their colocalization rate, whereas hyponatremic environment down-regulates complex activity via a decrease in the relative number of NaX channels controlled by the pump. PMID:25538563

Berret, Emmanuelle; Smith, Pascal Y.; Henry, Mélaine; Soulet, Denis; Hébert, Sébastien S.; Toth, Katalin; Mouginot, Didier; Drolet, Guy

2014-01-01

112

L'avifauna del Laghetto del Frassino (Peschiera del Garda, Verona, Veneto)  

Microsoft Academic Search

Ten years of ornithological research at Lake Frassino (located near Peschiera del Garda, Verona, Italy) have produced a check-list of the birds dwelling at this Site of Community Importance (S.I.C.) to be produced. Our surveys have revealed that this water basin where ducks stop al- most exclusively during the day represents, together with nearby Lake Garda, the most important wintering

MARCO MORBIOLI; MAURIZIO SIGHELE

113

Coulomb excitation of radioactive 20, 21Na  

NASA Astrophysics Data System (ADS)

The low-energy structures of the radioactive nuclei 20, 21Na have been examined using Coulomb excitation at the TRIUMF-ISAC radioactive ion beam facility. Beams of ˜ 5×106 ions/s were accelerated to 1.7MeV/A and Coulomb excited in a 0.5mg/cm^2 natTi target. Two TIGRESS HPGe clover detectors perpendicular to the beam axis were used for ? -ray detection, while scattered nuclei were observed by the Si detector BAMBINO. For 21Na , Coulomb excitation from the 3/2+ ground state to the first excited 5/2+ state was observed, while for 20Na , Coulomb excitation was observed from the 2+ ground state to the first excited 3+ and 4+ states. For both beams, B ( ? L) values were determined using the 2+ rightarrow 0+ de-excitation in 48Ti as a reference. The resulting B( E2) ? value for 21Na is 137±9 e^2fm^4, while the resulting B( ? L) ? values for 20Na are 55±6 e^2fm^4 for the 3+ rightarrow 2+ , 35.7±5.7 e^2 fm^4 for the 4+ rightarrow 2+ , and 0.154±0.030 ?_ N^2 for the 4+ rightarrow 3+ transitions. This analysis significantly improves the measurement of the 21Na B( E2) value, and provides the first experimental determination of B( ? L) values for the proton dripline nucleus 20Na .-1

Schumaker, M. A.; Cline, D.; Hackman, G.; Pearson, C.; Svensson, C. E.; Wu, C. Y.; Andreyev, A.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Becker, J. A.; Boston, A. J.; Boston, H. C.; Buchmann, L.; Churchman, R.; Cifarelli, F.; Cooper, R. J.; Cross, D. S.; Dashdorj, D.; Demand, G. A.; Dimmock, M. R.; Drake, T. E.; Finlay, P.; Gallant, A. T.; Garrett, P. E.; Green, K. L.; Grint, A. N.; Grinyer, G. F.; Harkness, L. J.; Hayes, A. B.; Kanungo, R.; Lisetskiy, A. F.; Leach, K. G.; Lee, G.; Maharaj, R.; Martin, J.-P.; Moisan, F.; Morton, A. C.; Mythili, S.; Nelson, L.; Newman, O.; Nolan, P. J.; Orce, J. N.; Padilla-Rodal, E.; Phillips, A. A.; Porter-Peden, M.; Ressler, J. J.; Roy, R.; Ruiz, C.; Sarazin, F.; Scraggs, D. P.; Waddington, J. C.; Wan, J. M.; Whitbeck, A.; Williams, S. J.; Wong, J.

2009-12-01

114

NMR studies on Na+ transport in Synechococcus PCC 6311  

NASA Technical Reports Server (NTRS)

The freshwater cyanobacterium Synechococcus PCC 6311 is able to adapt to grow after sudden exposure to salt (NaCl) stress. We have investigated the mechanism of Na+ transport in these cells during adaptation to high salinity. Na+ influx under dark aerobic conditions occurred independently of delta pH or delta psi across the cytoplasmic membrane, ATPase activity, and respiratory electron transport. These findings are consistent with the existence of Na+/monovalent anion cotransport or simultaneous Na+/H+ +anion/OH- exchange. Na+ influx was dependent on Cl-, Br-, NO3-, or NO2-. No Na+ uptake occurred after addition of NaI, NaHCO3, or Na2SO4. Na+ extrusion was absolutely dependent on delta pH and on an ATPase activity and/or on respiratory electron transport. This indicates that Na+ extrusion via Na+/H+ exchange is driven by primary H+ pumps in the cytoplasmic membrane. Cells grown for 4 days in 0.5 m NaCl medium, "salt-grown cells," differ from control cells by a lower maximum velocity of Na+ influx and by lower steady-state ratios of [Na+]in/[Na+]out. These results indicate that cells grown in high-salt medium increase their capacity to extrude Na+. During salt adaptation Na+ extrusion driven by respiratory electron transport increased from about 15 to 50%.

Nitschmann, W. H.; Packer, L.

1992-01-01

115

Ayuda para usar el sitio web en español del Instituto Nacional del Cáncer  

Cancer.gov

Página de guía que le permite al lector entender la forma en que está organizado el sitio web del Instituto Nacional del Cáncer (NCI), las categorías de información disponibles y las políticas que rigen este sitio web.

116

Evolucin del desarrollo y del costo de los sistemas fotovoltaicos en el mundo y en Chile  

E-print Network

Evolución del desarrollo y del costo de los sistemas fotovoltaicos en el mundo y en Chile Pontificia Universidad Católica de Chile Escuela de Ingeniería Departamento de Ingeniería Eléctrica IEE3372............................................................................................ 28 SMA Solar Technology

Rudnick, Hugh

117

l contenido econmico del XVI Con-greso del Partido Comunista Chino  

E-print Network

Organiza- ción Mundial del Comercio; Pekín ha sido ele- gida sede de los Juegos Olímpicos del 2008; el PCCh internacional, sino que la propia estruc- tura interna se configura según las prioridades de una economía

García-Berthou, Emili

118

Propostes i despropòsits: aspectes del gonellisme  

Microsoft Academic Search

Estudi sobre l'origen i la pervivència del gonellisme. Els autors n'exposen les constants ideològiques, que van del conservadorisme a l'extrema dreta, i fan una completa relació de les seves plataformes de difusió. L'anàlisi minuciosa d'aquest fenomen els porta a considerar el lligam entre el dialectalisme primigeni i el secessionisme anticatalanista que en deriva, així com a constatar la importància del

Guillem Calaforra; Sebastià Moranta

2005-01-01

119

El astrologo y el Emperador del Ganges1 Nota preliminar  

E-print Network

El astr´ologo y el Emperador del Ganges1 Nota preliminar El explorador y aventurero Sir Richard~nos las Actas de las audiencias del Emperador del Ganges, pero apenas logr´o recopilar algunos de los comunicante: Las audiencias del Emperador del Ganges eran re- gistradas en Actas, con todo lujo de detalles

Fernández Gallardo, Pablo

120

First-principles study of fast Na diffusion in Na3P  

NASA Astrophysics Data System (ADS)

We investigate the ionic conductivity and electronic properties of Na3P using first principle simulations. We found that the atoms were arranged in one layer of Na and P atoms and alternate layers containing Na atoms only. Three possible independent and asymmetric Na diffusion paths exist. In the first two, Na diffusion occurs among sodium atoms in the same layer, while in the third path, Na diffusion occurs among sodium atoms in different layers. Moreover, the activation energies of Na diffusion in the first two paths are much smaller than that of the third. With the introduction of a Na vacancy, a hole state deep in the valence region appears that is responsible for the valence band-edge rising in the center of the Brillouin zone. This sodium vacancy is very likely to play a role in the electron transfer in Na3P. The fast ionic conductivity and considerable electron conductivity make P a promising anode material in the first step of the Na deintercalation process.

Yu, Xue-fang; Giorgi, Giacomo; Ushiyama, Hiroshi; Yamashita, Koichi

2014-09-01

121

Characteristics and pharmacological regulation of epithelial Na+ channel (ENaC) and epithelial Na+ transport.  

PubMed

Epithelial Na(+) transport participates in control of various body functions and conditions: e.g., homeostasis of body fluid content influencing blood pressure, control of amounts of fluids covering the apical surface of alveolar epithelial cells at appropriate levels for normal gas exchange, and prevention of bacterial/viral infection. Epithelial Na(+) transport via the transcellular pathway is mediated by the entry step of Na(+) across the apical membrane via Epithelial Na(+) Channel (ENaC) located at the apical membrane, and the extrusion step of Na(+) across the basolateral membrane via the Na(+),K(+)-ATPase located at the basolateral membrane. The rate-limiting step of the epithelial Na(+) transport via the transcellular pathway is generally recognized to be the entry step of Na(+) across the apical membrane via ENaC. Thus, up-/down-regulation of ENaC essentially participates in regulatory systems of blood pressure and normal gas exchange. Amount of ENaC-mediated Na(+) transport is determined by the number of ENaCs located at the apical membrane, activity (open probability) of individual ENaC located at the apical membrane, single channel conductance of ENaC located at the apical membrane, and driving force for the Na(+) entry via ENaCs across the apical membrane. In the present review article, I discuss the characteristics of ENaC and how these factors are regulated. PMID:25242083

Marunaka, Yoshinori

2014-01-01

122

Characteristics and Pharmacological Regulation of Epithelial Na(+) Channel (ENaC) and Epithelial Na(+) Transport.  

PubMed

Epithelial Na(+) transport participates in control of various body functions and conditions: e.g., homeostasis of body fluid content influencing blood pressure, control of amounts of fluids covering the apical surface of alveolar epithelial cells at appropriate levels for normal gas exchange, and prevention of bacterial/viral infection. Epithelial Na(+) transport via the transcellular pathway is mediated by the entry step of Na(+) across the apical membrane via Epithelial Na(+) Channel (ENaC) located at the apical membrane, and the extrusion step of Na(+) across the basolateral membrane via the Na(+),K(+)-ATPase located at the basolateral membrane. The rate-limiting step of the epithelial Na(+) transport via the transcellular pathway is generally recognized to be the entry step of Na(+) across the apical membrane via ENaC. Thus, up-/down-regulation of ENaC essentially participates in regulatory systems of blood pressure and normal gas exchange. Amount of ENaC-mediated Na(+) transport is determined by the number of ENaCs located at the apical membrane, activity (open probability) of individual ENaC located at the apical membrane, single channel conductance of ENaC located at the apical membrane, and driving force for the Na(+) entry via ENaCs across the apical membrane. In the present review article, I discuss the characteristics of ENaC and how these factors are regulated. PMID:25152008

Marunaka, Yoshinori

2014-08-23

123

Catalysis of Na+ permeation in the bacterial sodium channel NaVAb  

PubMed Central

Determination of a high-resolution 3D structure of voltage-gated sodium channel NaVAb opens the way to elucidating the mechanism of ion conductance and selectivity. To examine permeation of Na+ through the selectivity filter of the channel, we performed large-scale molecular dynamics simulations of NaVAb in an explicit, hydrated lipid bilayer at 0 mV in 150 mM NaCl, for a total simulation time of 21.6 ?s. Although the cytoplasmic end of the pore is closed, reversible influx and efflux of Na+ through the selectivity filter occurred spontaneously during simulations, leading to equilibrium movement of Na+ between the extracellular medium and the central cavity of the channel. Analysis of Na+ dynamics reveals a knock-on mechanism of ion permeation characterized by alternating occupancy of the channel by 2 and 3 Na+ ions, with a computed rate of translocation of (6 ± 1) × 106 ions?s?1 that is consistent with expectations from electrophysiological studies. The binding of Na+ is intimately coupled to conformational isomerization of the four E177 side chains lining the extracellular end of the selectivity filter. The reciprocal coordination of variable numbers of Na+ ions and carboxylate groups leads to their condensation into ionic clusters of variable charge and spatial arrangement. Structural fluctuations of these ionic clusters result in a myriad of ion binding modes and foster a highly degenerate, liquid-like energy landscape propitious to Na+ diffusion. By stabilizing multiple ionic occupancy states while helping Na+ ions diffuse within the selectivity filter, the conformational flexibility of E177 side chains underpins the knock-on mechanism of Na+ permeation. PMID:23803856

Chakrabarti, Nilmadhab; Ing, Christopher; Payandeh, Jian; Zheng, Ning; Catterall, William A.; Pomès, Régis

2013-01-01

124

Cirugía de los trastornos del comportamiento: el estado del arte  

PubMed Central

Introducción: La cirugía de los trastornos del comportamiento (CTC) se está convirtiendo en un tratamiento más común desde el desarrollo de la neuromodulación. Métodos: Este artículo es una revisión no sistemática de la historia, indicaciones actuales, técnicas y blancos quirúrgicos de la CTC. Dividimos su historia en 3 eras: la primera comienza en los inicios de la psicocirugía y termina con el desarrollo de las tícnicas estereotácticas, cuando comienza la segunda era. Ésta se caracteriza por la realización de lesiones estereotácticas. Nos encontramos transitando la tercera era, que comienza cuando la estimulación cerebral profunda (ECP) comienza a ser usada en CTC. Resultados: A pesar de los errores graves cometidos en el pasado, hoy en día, la CTC está renaciendo. Los trastornos psiquiátricos que se más frecuentemente se tratan con cirugía son: depresión refractaria, trastorno obsesivo-compulsivo y síndrome de Tourette. Además, algunos pacientes con agresividad fueron tratados quirúrgicamente. Hay varios blancos estereotácticos descriptos para estos trastornos. La estimulación vagal puede ser usada también para depresión. Conclusión: Los resultados de la ECP en estos trastornos parecen alentadores. Sin embargo, se necesitan más estudios randomizados para establecer la efectividad de la CTC. Debe tenerse en cuenta que una apropiada selección de pacientes nos ayudará a realizar un procedimiento más seguro así como también a lograr mejores resultados quirúrgicos, conduciendo a la CTC a ser más aceptada por psiquiatras, pacientes y sus familias. Se necesita mayor investigación en varios temas como: fisiopatología de los trastornos del comportamiento, indicaciones de CTC y nuevos blancos quirúrgicos. PMID:25165612

Yampolsky, Claudio; Bendersky, Damián

2014-01-01

125

Research Note--Computational Identification of Reassortments  

E-print Network

in reassortment identification of NP segments in H5N1 AIVs. We identified two new potential reassortments for H5N1 los segmentos del gen de la nucleoprotei´na provenientes de virus H5N1 de influenza aviar. Se logro´ la identificacio´n de dos recombinaciones potenciales para los virus H5N1 de influenza aviar, mas

Lin, Guohui

126

La arquitectura del pastoreo: Uso del espacio y sistema de asentamientos en la Puna de Atacama (Susques)  

Microsoft Academic Search

RESUMEN El objetivo del trabajo es contribuir al conocimiento de la arquitectura del pastoreo en los Andes. El foco regio- nal del estudio es Huancar en el Departamento Susques (Jujuy, Argentina). En primer lugar se describen los sis- temas de asentamientos vinculados con las actividades pastoriles de Huancar y luego se presentan los esquemas del uso del espacio por parte

Barbara Göbel

2002-01-01

127

Erythrocyte 22Na+ influx in hypertension  

SciTech Connect

We assessed 22Na+ uptake by erythrocytes (RBC) from 38 individuals with essential hypertension and 37 healthy controls. All subjects were male, white, non-obese and with normal renal function, obviating sex, race, hormonal, ponderal and renal factors known to influence RBC Na+ handling. The mean +/- sem 22Na+ uptake of the patients was 284 +/- 16 mumole/liter RBC/hour while that of normal controls was 249 +/- 11 mumole/liter RBC/hour; although the difference reached borderline significance, individual values showed considerable overlap. Consequently, in our population, RBC 22Na+ uptake is not a reliable marker for essential hypertension. We believe that previous studies should be reassessed with regard to patients' characteristics and future studies employ rigorous criteria in selection of subjects.

Shalev, O.; Eaton, J.W.; Ben-Ishay, D.

1984-01-01

128

Hydrogen-fluorine exchange in NaBH4-NaBF4.  

PubMed

Hydrogen-fluorine exchange in the NaBH4-NaBF4 system is investigated using a range of experimental methods combined with DFT calculations and a possible mechanism for the reactions is proposed. Fluorine substitution is observed using in situ synchrotron radiation powder X-ray diffraction (SR-PXD) as a new Rock salt type compound with idealized composition NaBF2H2 in the temperature range T = 200 to 215 °C. Combined use of solid-state (19)F MAS NMR, FT-IR and DFT calculations supports the formation of a BF2H2(-) complex ion, reproducing the observation of a (19)F chemical shift at -144.2 ppm, which is different from that of NaBF4 at -159.2 ppm, along with the new absorption bands observed in the IR spectra. After further heating, the fluorine substituted compound becomes X-ray amorphous and decomposes to NaF at ~310 °C. This work shows that fluorine-substituted borohydrides tend to decompose to more stable compounds, e.g. NaF and BF3 or amorphous products such as closo-boranes, e.g. Na2B12H12. The NaBH4-NaBF4 composite decomposes at lower temperatures (300 °C) compared to NaBH4 (476 °C), as observed by thermogravimetric analysis. NaBH4-NaBF4 (1:0.5) preserves 30% of the hydrogen storage capacity after three hydrogen release and uptake cycles compared to 8% for NaBH4 as measured using Sievert's method under identical conditions, but more than 50% using prolonged hydrogen absorption time. The reversible hydrogen storage capacity tends to decrease possibly due to the formation of NaF and Na2B12H12. On the other hand, the additive sodium fluoride appears to facilitate hydrogen uptake, prevent foaming, phase segregation and loss of material from the sample container for samples of NaBH4-NaF. PMID:24071912

Rude, L H; Filsø, U; D'Anna, V; Spyratou, A; Richter, B; Hino, S; Zavorotynska, O; Baricco, M; Sørby, M H; Hauback, B C; Hagemann, H; Besenbacher, F; Skibsted, J; Jensen, T R

2013-11-01

129

Characterization of Synthetic Na-Beidellite  

Microsoft Academic Search

Ahstract--Na-beidellite, a member of the smectite group, was grown hydrothermally from a gel of composition 0.35NazO.2.35A1zO3.7.3SiO2 in NaOH solutions at a pH between 7.5 and 13.5, a pressure of 1 kbar, and a temperature of 350\\

J. THEO K-LOPROGGE; BEN H. JANSEN; JOHN W. GEUS

1990-01-01

130

Deliquescence of NaCl-NaNO3, KNO3-NaNO3, and NaCl-KNO3 Salt Mixtures From 90 to 120?C  

SciTech Connect

We conducted reversed deliquescence experiments in saturated NaCl-NaNO{sub 3}-H{sub 2}O, KNO{sub 3}-NaNO{sub 3}-H{sub 2}O, and NaCl-KNO{sub 3}-H{sub 2}O systems from 90 to 120 C as a function of relative humidity and solution composition. NaCl, NaNO{sub 3}, and KNO{sub 3} represent members of dust salt assemblages that are likely to deliquesce and form concentrated brines on high-level radioactive waste package surfaces in a repository environment at Yucca Mountain, NV, USA. Discrepancy between model prediction and experimental code can be as high as 8% for relative humidity and 50% for dissolved ion concentration. The discrepancy is attributed primarily to the use of 25 C models for Cl-NO{sub 3} and K-NO{sub 3} ion interactions in the current Yucca Mountain Project high-temperature Pitzer model to describe the non-ideal behavior of these highly concentrated solutions.

Carroll, S A; Craig, L; Wolery, T J

2004-10-20

131

PROVA PRATICA Valutazione economica di un Piano attuativo del PRG  

E-print Network

PROVA PRATICA Valutazione economica di un Piano attuativo del PRG In presenza di un Piano attuativo'intera previsione volumetrica (commerciale e residenziale) del Piano attuativo, sia delle urbanizzazioni primarie e valutazione di compatibilita urbanistica del Piano attuativo #12;

Di Pillo, Gianni

132

Control del dolor: Apoyo para las personas con cáncer  

Cancer.gov

Libro sobre el control del dolor en pacientes con cáncer. Cubre los métodos y medicinas, así como los efectos físicos y emocionales del dolor. Es una adaptación cultural para el público de habla hispana del libro en inglés Pain Control.

133

Determination of Na acceptor level in Na+ ion-implanted ZnO single crystal  

NASA Astrophysics Data System (ADS)

Ion implantation was used to dope Na acceptor into ZnO single crystals. With three mixed implantation energies, uniform depth distribution of Na ion in the surface region (~300 nm) of ZnO bulk crystals is achieved. Via post-implantation annealing, a donor-acceptor pair recombination band is identified in the low-temperature photoluminescence spectra, from which the energy level of Na-related acceptor in single crystalline ZnO is estimated to be 300 meV. A p-n junction based on this ZnO-Na layer shows rectifying characteristics, confirming the p-type conductivity.

Wang, Zheng; Liu, Huibin; He, Haiping; Huang, Jingyun; Chen, Lingxiang; Ye, Zhizhen

2015-03-01

134

Inactivation of Rb+ and Na+ occlusion on (Na+,K+)-ATPase by modification of carboxyl groups.  

PubMed

This paper demonstrates and characterizes inactivation by N,N'-dicyclohexylcarbodiimide (DCCD) of Rb+ and Na+ occlusion in pig kidney (Na+,K+)-ATPase. Rb+ and Na+ occlusion dependent on oligomycin are measured with a manual assay. Parallel measurement of phosphorylation (by Pi plus ouabain) and Na+ or Rb+ occlusion lead to stoichiometries of 3 Na+ or 2 Rb+ per pump molecule. Inactivation of cation occlusion by DCCD shows the following features: (a) Rb+ and Na+ occlusion are inactivated with identical rates and (b) DCCD concentration dependence shows first-order kinetics and also proportionality to the ratio of DCCD to protein, (c) Rb+ and Na+ occlusion are equally protected from DCCD, by Rb+ ions with high affinity (or Na+ ions with lower affinity), (d) inactivation is only slightly pH-dependent between 6 and 8.5 but (e) is significantly accelerated by several hydrophobic amines while a water-soluble nucleophile, glycine ethyl ester has no effect, and (f) inactivation is exactly correlated with inactivation of (Na+,K+)-ATPase activity of ATP-dependent Na+/K+ exchange in reconstituted vesicles and with the magnitude of E1Na+----E2(Rb+) conformational transitions measured with fluorescence probes. The simplest hypothesis to explain the results is that DCCD modifies one (or a small number of) critical carboxyl residues in a non-aqueous cation binding domain and so blocks occlusion of 2 Rb+ or 3 Na+ ions. The results suggest further that Na+ and K+(Rb+) bind to the same sites and are transported sequentially on the same trans-membrane segments. A second effect of the DCCD treatment is a 4-8-fold shift of the conformational equilibrium E2(Rb+)----E1Rb+ toward E1Rb+. This is detected by (a) reduction in apparent Rb+ affinity for Rb+ occlusion or Rb+/Rb+ exchange in vesicles and (b) direct demonstration of an increased rate of E2(K+)----E1Na+ and decreased rate of E1Na+----E2(K+). This effect is not protected against by Rb+ ions and probably reflects modification of a second group of residues. Modification of (Na+,K+)-ATPase by carbodiimides is complex. Depending on the nature of the carbodiimide (water- or lipid-soluble), ratio of carbodiimide to protein, and perhaps source of the enzyme, inactivation might result either from modification of critical carboxyls, as suggested by this work, or from internal cross-linking as proposed by Pedemonte, C. H. and Kaplan, J. H. ((1986) J. Biol. Chem. 261, 3632-3639). PMID:2848822

Shani-Sekler, M; Goldshleger, R; Tal, D M; Karlish, S J

1988-12-25

135

Monsters begat by quantifiers? Fabio Del Prete  

E-print Network

Monsters begat by quantifiers? Fabio Del Prete CNRS Lab CLLE-ERSS Toulouse Sandro Zucchi apparent consequence of this approach is that quantifiers and s are monsters in Kaplan's sense. We argue-00965284,version1-24Mar2014 #12;F. Del Prete - S. Zucchi Monsters begat by quantifiers? While some

Paris-Sud XI, Université de

136

Fisiología del embarazo: Interacción materno-infantil  

Microsoft Academic Search

ResumenEn los últimos años los datos han demostrado de qué manera el bienestar vitalicio depende considerablemente del crecimiento y el desarrollo intrauterinos durante la vida dentro del útero. El crecimiento fetal puede alcanzar únicamente su potencial íntegro mediante una interacción adecuada y armonizada entre la madre, la placenta y el feto. Este delicado equilibrio puede ser alterado por varios factores

Irene Cetin; Manuela Cardellicchio

2010-01-01

137

Las culturas políticas del republicanismo histórico español  

Microsoft Academic Search

Desde la perspectiva teórica denominada «Giro cultural», hemos tratado de repensar la formación del movimiento republicano español durante el siglo XIX, el cual tradicionalmente ha sido concebido de forma unívoca. En realidad, varios movimientos sociales coexistieron dentro del republicanismo español. Al menos desde tres culturas políticas republicanas (socialismo jacobino, demosocialismo y demoliberalismo) fueron movilizadas las clases populares españolas y se

Román Miguel González

2004-01-01

138

Svelato il codice genetico del lievito enologico  

Microsoft Academic Search

Primi al mondo, i ricercatori del 'The Australian Wine Research Institute' hanno completato il sequenziamento del genoma di un lievito enologico, descrivendo le 'ricette vitali' che danno forma all'amico dell'enologo. Questa ricerca apre la strada allo sviluppo di nuovi ceppi di lievito, in grado di offrire soluzioni innovative per il problema degli arresti di fermentazione, e di aumentare la gamma

Anthony R. Borneman; Angus H. Forgan; Paul J. Chambers; Isak S. Pretorius

139

Aspectos macroeconómicos del plan de desarrollo  

Microsoft Academic Search

Poco después de la apertura, la economía inició un ciclo de crecimiento rápido y acumulación de déficits, seguido por otra etapa de correctivos monetarios que frenan el crecimiento, pero que no eliminan las causas del desiquilibrio. El Plan de Desarrollo reduce el déficit fiscal y es probable que la próxima fase de expansión dure 3 años, en lugar del año

Luis Lorente

1999-01-01

140

Aspectos generales del concepto “capital humano”  

Microsoft Academic Search

ReSUMeN El presente artículo es la síntesis del debate de los autores sobre las transformaciones organizacionales basadas en el creciente predominio de los activos intangibles, especialmente del capital humano, para comprender las organizaciones económicas actuales en medio de sus contextos altamente exigentes y variables, como resultado de la fase inicial de una investigación general sobre el factor trabajo de las

Camilo Ernesto Tinoco Bernal; Sylvia Melissa Soler Mantilla

2011-01-01

141

Banco de Proyectos del Decanato de Extensin  

E-print Network

bienes a precios solidarios o al costo Aporte en especies a programas sociales determinados por el apoyan la propuesta 10. Resumen del presupuesto del proyecto. (Monto en BsF) Indique el financiamiento requerido para que la idea pueda lograr los objetivos mencionados. Costo total de la propuesta Monto

Vásquez, Carlos

142

CAPÍTULO 4. ANÁLISIS DEL DISCURSO: DISCURSO DEL EMPERADOR HIROHITO CON MOTIVO DE LA RENDICIÓN DE JAPÓN DE LA GUERRA DEL PACÍFICO  

Microsoft Academic Search

El ACD se encuadra en el marco teórico del Análisis del Discurso, teoría que otorga al discurso la dimensión de práctica social. En el ACD se explota esta vertiente social del uso del lenguaje, profundizando en las relaciones sociales e ideológicas que se establecen entre el texto y el contexto. El discurso se concibe como un concepto tridimensional: discurso como

Raquel Rubio Martín

143

XI INTI International Conference La Plata 2012 Equipo TAG Territorios Posibles UNLP-CONICET y Universidades asociadas del GDRI  

E-print Network

midiáticos oriundos da era pré-internet - como livros, filmes e videogames - pela rede, relacionando-o com de produtos midiáticos provenientes de tecnologias pré-internet - como livros, filmes e videogames

Boyer, Edmond

144

Nonresonant charge-capture - Na/+/ + Li reversibly proceeding to Na + Li/+/.  

NASA Technical Reports Server (NTRS)

The cross sections for the process Na(+) + Li reversibly proceeding to Na + Li(+) are calculated in the range from 100 eV to 12 keV using a perturbed stationary state formulation, and are found to agree with experiment to the extent of reproducing detailed structure. A simple interpretation is presented of the observed quasi-oscillatory structure.

Bottcher, C.; Oppenheimer, M.

1972-01-01

145

Na-ion dynamics in Quasi-1D compound NaV2O4  

NASA Astrophysics Data System (ADS)

We have used the pulsed muon source at ISIS to study high-temperature Na-ion dynamics in the quasi-one-dimensional (Q1D) metallic antiferromagnet NaV2O4. By performing systematic zero-field and longitudinal-field measurements as a function of temperature we clearly distinguish that the hopping rate increases exponentially above Tdiff ? 250 K. The data is well fitted to an Arrhenius type equation typical for a diffusion process, showing that the Na-ions starts to be mobile above Tdiff. Such results make this compound very interesting for the tuning of Q1D magnetism using atomic-scale ion-texturing through the periodic potential from ordered Na-vacancies. Further, it also opens the door to possible use of NaV2O4 and related compounds in energy related applications.

Månsson, M.; Umegaki, I.; Nozaki, H.; Higuchi, Y.; Kawasaki, I.; Watanabe, I.; Sakurai, H.; Sugiyama, J.

2014-12-01

146

The voltage-gated Na channel NaVBP has a role in motility, chemotaxis, and pH homeostasis  

E-print Network

The voltage-gated Na channel NaVBP has a role in motility, chemotaxis, and pH homeostasisH homeostasis at high pH. Reduced motility of bacteria lacking functional NaVBP was reversed by restoration in response to chemoeffectors. Mutants lacking functional NaVBP were also defective in pH homeostasis

Clapham, David E.

147

Functional coupling of renal K+ and Na+ handling causes high blood pressure in Na+ replete mice  

PubMed Central

A network of kinases, including WNKs, SPAK and Sgk1, is critical for the independent regulation of K+ and Na+ transport in the distal nephron. Angiotensin II is thought to act as a key hormone in orchestrating these kinases to switch from K+ secretion during hyperkalaemia to Na+ reabsorption during intravascular volume depletion, thus keeping disturbances in electrolyte and blood pressure homeostasis at a minimum. It remains unclear, however, how K+ and Na+ transport are regulated during a high Na+ intake, which is associated with suppressed angiotensin II levels and a high distal tubular Na+ load. We therefore investigated the integrated blood pressure, renal, hormonal and gene and protein expression responses to large changes of K+ intake in Na+ replete mice. Both low and high K+ intake increased blood pressure and caused Na+ retention. Low K+ intake was accompanied by an upregulation of the sodium-chloride cotransporter (NCC) and its activating kinase SPAK, and inhibition of NCC normalized blood pressure. Renal responses were unaffected by angiotensin AT1 receptor antagonism, indicating that low K+ intake activates the distal nephron by an angiotensin-independent mode of action. High K+ intake was associated with elevated plasma aldosterone concentrations and an upregulation of the epithelial sodium channel (ENaC) and its activating kinase Sgk1. Surprisingly, high K+ intake increased blood pressure even during ENaC or mineralocorticoid receptor antagonism, suggesting the contribution of aldosterone-independent mechanisms. These findings show that in a Na+ replete state, changes in K+ intake induce specific molecular and functional adaptations in the distal nephron that cause a functional coupling of renal K+ and Na+ handling, resulting in Na+ retention and high blood pressure when K+ intake is either restricted or excessively increased. PMID:24396058

Vitzthum, Helga; Seniuk, Anika; Schulte, Laura Helene; Müller, Maxie Luise; Hetz, Hannah; Ehmke, Heimo

2014-01-01

148

Targeting voltage gated sodium channels NaV1.7, Na V1.8, and Na V1.9 for treatment of pathological cough.  

PubMed

Recent advances in our understanding of voltage-gated sodium channels (NaVs) lead to the rational hypothesis that drugs capable of selective blockade of NaV subtypes may be a safe and effective strategy for the treatment of unwanted cough. Among the nine NaV subtypes (NaV1.1-NaV1.9), the afferent nerves involved in initiating cough, in common with nociceptive neurons in the somatosensory system, express mainly NaV1.7, NaV1.8, and NaV1.9. Although knowledge about the effect of selectively blocking these channels on the cough reflex is limited, their biophysical properties indicate that each may contribute to the hypertussive and allotussive state that typifies subacute and chronic nonproductive cough. PMID:24272479

Muroi, Yukiko; Undem, Bradley J

2014-02-01

149

Intracellular [Na+], Na+ pathways, and fluid transport in cultured bovine corneal endothelial cells.  

PubMed

The mechanism of fluid transport across corneal endothelium remains unclear. We examine here the relative contributions of cellular mechanisms of Na+ transport and the homeostasis of intracellular [Na+] in cultured bovine corneal endothelial cells, and the influence of ambient Na+ and HCO3- on the deturgescence of rabbit cornea. Bovine corneal endothelial cells plated on glass coverslips were incubated for 60 min with 10 microm of the fluorescent Na+ indicator SBFI precursor in HCO3- HEPES (BH) Ringer's solution. After loading, cells were placed in a perfusion chamber. Indicator fluorescence (490 nm) was determined with a Chance-Legallais time-sharing fluorometer. Its voltage output was the ratio of the emissions excited at 340 and 380 nm. For calibration, cells were treated with gramicidin D. For fluid transport measurements, rabbit corneas were mounted in a Dikstein-Maurice chamber, and stromal thickness was measured with a specular microscope. The steady-state [Na+]i in BH was 14.36+/-0.38 mM (n = mean+/-s.e.). Upon exposure to Na+ -free BH solution (choline substituted), [Na+]i decreased to 1.81+/-0.20mM (n = 19). When going from Na+ -free plus 100 microm ouabain to BH plus ouabain, [Na+]i increased to 46.17+/-2.50 (n = 6) with a half time of 1.26+/-0.04 min; if 0.1 microm phenamil plus ouabain were present, it reached only 21.78+/-1.50mm. The exponential time constants (min-1) were: 0.56+/-0.04 for the Na+ pump; 0.39+/-0.01 for the phenamil sensitive Na+ channel; and 0.17+/-0.02 for the ouabain-phenamil-insensitive pathways. In HCO3- free medium (gluconate substituted), [Na+]i was 14.03+/-0.11mM; upon changing to BH medium, it increased to 30.77+/-0.74 mm. This last [Na+]i increase was inhibited 66% by 100 microm DIDS. Using BH medium, corneal thickness remained nearly constant, increasing at a rate of only 2.9+/-0.9 microm hr-1 during 3 hr. However, stromal thickness increased drastically (swelling rate 36.1+/-2.6 microm hr-1) in corneas superfused with BH plus 100 microm ouabain. Na+ -free, HCO3- free solution and 100 microm DIDS also led to increased corneal swelling rates (17.7+/-3.6, 14.4+/-1.6 and 14.9+/-1.2 microm hr-1, respectively). The present results are explained by the presence of a DIDS-inhibitable Na+-HCO3- cotransporter and an epithelial Na+ channel, both previously found in these cells. On the other hand, the quantitative picture presented here appears a novelty. The changes we observe are consistent with pump-driven rapid exchange of intracellular Na+, and recirculation of fully 70% of the Na+ pump flux via apical Na+ channels. PMID:15183104

Kuang, Kunyan; Li, Yansui; Yiming, Maimaiti; Sánchez, José M; Iserovich, Pavel; Cragoe, E J; Diecke, Friedrich P J; Fischbarg, Jorge

2004-07-01

150

COMUNICATO STAMPA Analisi Applicata del Comportamento (ABA) ed Autismo  

E-print Network

COMUNICATO STAMPA Analisi Applicata del Comportamento (ABA) ed Autismo Data Scadenza: 10 giugno 2014 ANALISI APPLICATA DEL COMPORTAMENTO (ABA) ED AUTISMO L'Università di Salerno ha pubblicati i bandi trattamento dei bambini con autismo secondo i criteri del metodo ABA (Analisi Applicata del Comportamento). I

Costagliola, Gennaro

151

D.R. n. n. 5024 del 1.08.2011n. 5024 del 1.08.2011n. 5024 del 1.08.2011n. 5024 del 1.08.2011 ClasseClasseClasseClasse LM-6 -Biologia  

E-print Network

.08.2011 ClasseClasseClasseClasse LM-6 - Biologia Nome del corsoNome del corsoNome del corsoNome del corso BIOLOGIA AMBIENTALE Nome ingleseNome ingleseNome ingleseNome inglese ENVIRONMENTAL BIOLOGY Lingua in cui si/2010, art. 14) Obiettivi formativi qualificanti della classe: LM-6 Biologia I laureati nei corsi di laurea

Malerba, Donato

152

PROPUESTA DELIQUIDACIÓN DEL CONTRATO CONSTRUCCIÓN NUEVO ALCANTARILLADO DEBOCAGRANDE-CARTAGENA  

Microsoft Academic Search

El Centro de Investigaciones para el Desarrollo (CID) de la Facultad de Ciencias Económicas fue invitado para que emitiera un concepto técnico sobre la liquidación del contrato celebrado el 20 de agosto de 1998 entre el Departamento Administrativo de Valorización del Distrito de Cartagena (DAVD) y la Compañía Alcantarillado Bocagrande S.A. El objetivo del contrato es la construcción del nuevo

Jorge Ivan GonzalesBorrero; Edna Cristina del SocorroBonilla Sebá; German GuerreroChaparro

2005-01-01

153

Departament de Cincies del Mar i Biologia Aplicada Vdeo promoci estudis en Cincies del Mar  

E-print Network

Departament de Ciències del Mar i Biologia Aplicada Vídeo promoció estudis en Ciències del Mar en la província alacantina. Departament de Ciències del Mar i Biologia Aplicada #12;Magazine Oceà nº curs està orientat a gestors ambientals, investigadors, persones amb formació acadèmica en Biologia

Escolano, Francisco

154

Na+ inhibits the epithelial Na+ channel by binding to a site in an extracellular acidic cleft.  

PubMed

The epithelial Na(+) channel (ENaC) has a key role in the regulation of extracellular fluid volume and blood pressure. ENaC belongs to a family of ion channels that sense the external environment. These channels have large extracellular regions that are thought to interact with environmental cues, such as Na(+), Cl(-), protons, proteases, and shear stress, which modulate gating behavior. We sought to determine the molecular mechanism by which ENaC senses high external Na(+) concentrations, resulting in an inhibition of channel activity. Both our structural model of an ENaC ? subunit and the resolved structure of an acid-sensing ion channel (ASIC1) have conserved acidic pockets in the periphery of the extracellular region of the channel. We hypothesized that these acidic pockets host inhibitory allosteric Na(+) binding sites. Through site-directed mutagenesis targeting the acidic pocket, we modified the inhibitory response to external Na(+). Mutations at selected sites altered the cation inhibitory preference to favor Li(+) or K(+) rather than Na(+). Channel activity was reduced in response to restraining movement within this region by cross-linking structures across the acidic pocket. Our results suggest that residues within the acidic pocket form an allosteric effector binding site for Na(+). Our study supports the hypothesis that an acidic cleft is a key ligand binding locus for ENaC and perhaps other members of the ENaC/degenerin family. PMID:25389295

Kashlan, Ossama B; Blobner, Brandon M; Zuzek, Zachary; Tolino, Michael; Kleyman, Thomas R

2015-01-01

155

High-resolution molecular-beam spectroscopy of NaCN and Na 13CN  

NASA Astrophysics Data System (ADS)

The sodium cyanide molecule was studied by molecular-beam electric-resonance spectroscopy in the microwave region. We used the seeded-beam technique to produce a supersonic beam with strong translational, rotational and vibrational cooling. In the frequency range 9.5-40 GHz we observed and identified for NaCN 186 and for Na 13CN 107 hyperfine transitions in 20 and 16 rotational transitions, respectively, all in the ground vibrational state. The rotational, the five quartic and three sextic centrifugal distortion constants of NaCN are: A? = 57921.954(7) MHz; B? = 8369.312(2) MHz, C? = 7272.712(2) MHz. All quadrupole and several spin-rotation coupling constants for the hyperfine interaction were evaluated. The quadrupole coupling constants (in MHz) for NaCN are: eQq12(Na) = -5.344(5), eQq12 = 2.397(7). eQq12(N) = 2.148(4), eQq12(N) = -4.142(5). From these constants and those of Na 13CN we have determined the principal components of the quadrupole coupling tensor for potassium and nitrogen. The structure of sodium cyanide evaluated from the rotational constants of NaCN and Na 13CN was found to be T shaped, similar to the structure of KCN but completely different from the linear isocyanide configuration of LiNC. The effective structural parameters for sodium cyanide in the ground vibrational state are: rCN = 1.170(4) Å, rNaC = 2.379(15) Å, rN12N = 2.233(15) Å, in gratifying agreement with ab initio calculations. Both the geometrical structure and the hyperfine coupling justify the conclusion that the CN group in gaseous sodium cyanide approximately can be considered as a free CN - ion.

van Vaals, J. J.; Meerts, W. Leo; Dymanus, A.

156

UNIVERSIDAD SIMON BOLIVAR SEDE DEL LITORAL  

E-print Network

UNIVERSIDAD SIMON BOLIVAR SEDE DEL LITORAL ESPECIALIZACIÓN EN TELECOMUNICACIONES DECANATO DE POSTGRADO DENOMINACIÓN: CÓDIGO: ASIGNATURA: LABOR. DE TELECOMUNICACIONES TI-7341 REQUISITOS: H. TEORÍA: H Laboratorio de Telecomunicaciones, el estudiante deberá haber obtenido destrezas prácticas en los

Vásquez, Carlos

157

PROT. N. 00113811 Del 06 luglio 2006  

E-print Network

'anno 2006 dei bilanci di enti ed organismi pubblici, ivi comprese le Università e i Dipartimenti, relativi impegnate alla data di entrata in vigore del decreto. Lo stesso Decreto Legge dispone che le somme

Milano-Bicocca, Università

158

The role of Na/+/ in transport processes of bacterial membranes  

NASA Technical Reports Server (NTRS)

Until recently it was generally held that transport in bacteria was linked exclusively to proton circulation, in contrast to most eucaryotic systems, which depended on Na(+) circulation. The present review is intended to trace recent developments which have led to the discarding of this idea. The discussion covers transport of Na(+) and other cations, effects of Na(+) and Na(+) gradients on metabolite transport, properties of Na(+)-dependent transport carriers, and evolutionary considerations of Na(+) transport. It is now apparent that the transport of Na(+) is an important part of energy metabolism in bacteria, and that Na(+) gradients as well as H(+) gradients are used in these systems for the conservation and transmission of energy. Two hypotheses are proposed to explain the evolution of Na/K systems, and it is presently difficult to decide between them.

Lanyi, J. K.

1979-01-01

159

OCENA PODATNO ?CI PËATKÓW OWSIANYCH NA KRUSZENIE  

Microsoft Academic Search

S t r e s z c z e n i e . Celem pracy byo okre ?lenie wytrzymao ?ci kinetycznej patków owsianych byskawicznych. W pracy przedstawiono zakres zmian ksztatu i struktury badanych patków pod k?tem oceny ich podatno ?ci na kruszenie podczas testowania w testerze pneumatycznym i mecha- nicznym. Uzyskane wyniki bada ? obejmuj? zmiany cech geometrycznych patków, jakie

Marian Panasiewicz; Agnieszka Misiura

160

master's degree NaNotechNology  

E-print Network

master's degree NaNotechNology When choosing a Master's programme, it is wise to look one step topical, incorporating the latest developments in applied physics, nanotechnology, chemical engineering projects will be carried out at the MESA+ institute for nanotechnology, or the MIRA institute

Twente, Universiteit

161

Balance del año teatral 1972 en Lima.  

E-print Network

universitarios como el de la Universidad Villarreal y el de la Universidad San Martín de Porres y con grupos universitarios voca- cionales, como son el TUNI (Teatro de la Universidad Nacional, de Ingeniería) el ISANM o grupo de teatro del Instituto Superior de...), 33-41. 12. El Ingeniero Arturo Nolte, también director de producción del Teatro Nacional Popular, quien gentilmente nos brindó esta información, en entrevista celebrada en Lima, el 8 de mayo de 1972 puso de relieve que los grupos universitarios...

Cajiao Salas, Teresa

1974-10-01

162

La evolucion del modernismo en Puerto Rico  

E-print Network

elementos estilis- ticos: la belleza plastica, la musicalidad, el croma- tismo, el sensualismo, el exotismo, la evasion, el sen- tido cosmopolita y el dualismo. El modernismo ademas in- novo la metrica mediante el uso de los siguientes metros: los... por resaltar lo exotico, lo extravagante y lo pictorico. Hace uso de la parodia y de la shtira, pero cuidando de la forma y del ritmo del verso. De igual modo, Amado Nervo ejercio su influencia mediante su poesia existencialista y espiri- tualista...

Gonzalez-Hernandez, Miriam Mercedes

1989-01-01

163

Reseña del VIII Festival Internacional de Teatro  

E-print Network

los diferentes medios del país. Este vacío que fue protuberante se debió a la falta de recursos económicos para sostener esta clase de invitados. Mas como efecto positivo se percibió que durante la semana del evento el Festival Internacional no giró... una acción viva que requiere de crónica aparte. El Teatro Taller de Colombia merece página aparte por la validez e importancia de su trabajo que es toda una propuesta que cobija factores de indudable calidad, en especial su "circo invisible" que...

Dí az, Né stor Gustavo

1986-10-01

164

Gonadal dysgenesis in del (18p) syndrome  

SciTech Connect

We report on a girl with syndromal gonadal dysgenesis and a de novo del (18p). Genetic factors controlling gonadal development are located not only on the X chromosome, but also on autosomes. The present case suggests that one of these genes is situated on 18p. We conclude that patients with del (18p) syndrome should be evaluated for gonadal dysgenesis. 16 refs., 3 figs.

Telvi, L.; Ion, A.; Fouquet, F. [Hospital Saint Vincent de Paul, Paris (France)] [and others

1995-07-17

165

Pgina 1 de 18 CDIGO DE CONDUCTA DEL CENTRO DE  

E-print Network

Página 1 de 18 C�DIGO DE CONDUCTA DEL CENTRO DE INVESTIGACION Y DE ESTUDIOS AVANZADOS DEL INSTITUTO CONDUCTA: I. Conocimiento y aplicación de las leyes y normas. 1 II. Uso del cargo público. 2 III. Uso y T�RMINOS. 13 #12;Página 2 de 18 C�DIGO DE CONDUCTA DEL CENTRO DE INVESTIGACION Y DE ESTUDIOS AVANZADOS DEL

166

Calidad de Imagen del Telescopio UNAM212  

NASA Astrophysics Data System (ADS)

El telescopio UNAM2l2, del Observatorio Astronómico Nacional, situado en la Sierra de San Pedro Mártir (Baja California, México), cumplira en un futuro muy cercano siete años de uso para fines de investigación astronómica. Aunque en este tiempo no se ha efectuado un estudio sistemático acerca de su comportamiento óptico y de los factores que influyen en la calidad de las imágenes, se han realizado pruebas diversas, estudios parciales y reuniones especificas, cuyos resultados no siempre se han difundido ampliamente y generalmente no se han presentado por escrito. Es por ello que hemos creido necesario intentar una recopilación de la información existente para poder con ella establecer un diagnóstjco que, aunque no sea definitivo, sirva de base para futuros trabajos tendientes a optimizar el comportamiento óptico del telescopio. Es evidente que un buen número de las conclusiones que se presentan son resultado del trabajo de muchas personas ó de esfuerzos colectivos. Asimismo, hemos tratado de localizar información bibliográfica que pueda ser de utilidad. Nuestro objetivo primordial ha consistido en centrarnos en la óptica del telescopio y su calidad, pero también se han considerado otros aspectos que puedan afectar las imágenes obtenidas tales como: celda del primario, `seeing' local y externo, flexiones posibles en la estructura mecánica del telescopio, etc.

Cobos, F. J.; Teiada de Vargas, C.

1987-05-01

167

Laser trapping of {sup 21}Na atoms  

SciTech Connect

This thesis describes an experiment in which about four thousand radioactive {sup 21}Na (t{sub l/2} = 22 sec) atoms were trapped in a magneto-optical trap with laser beams. Trapped {sup 21}Na atoms can be used as a beta source in a precision measurement of the beta-asymmetry parameter of the decay of {sup 21}Na {yields} {sup 21}Ne + {Beta}{sup +} + v{sub e}, which is a promising way to search for an anomalous right-handed current coupling in charged weak interactions. Although the number o trapped atoms that we have achieved is still about two orders of magnitude lower than what is needed to conduct a measurement of the beta-asymmetry parameter at 1% of precision level, the result of this experiment proved the feasibility of trapping short-lived radioactive atoms. In this experiment, {sup 21}Na atoms were produced by bombarding {sup 24}Mg with protons of 25 MeV at the 88 in. Cyclotron of Lawrence Berkeley Laboratory. A few recently developed techniques of laser manipulation of neutral atoms were applied in this experiment. The {sup 21}Na atoms emerging from a heated oven were first transversely cooled. As a result, the on-axis atomic beam intensity was increased by a factor of 16. The atoms in the beam were then slowed down from thermal speed by applying Zeeman-tuned slowing technique, and subsequently loaded into a magneto-optical trap at the end of the slowing path. The last two chapters of this thesis present two studies on the magneto-optical trap of sodium atoms. In particular, the mechanisms of magneto-optical traps at various laser frequencies and the collisional loss mechanisms of these traps were examined.

Lu, Zheng-Tian

1994-09-01

168

Sodium thioether macrocyclic chemistry: remarkable homoleptic octathia coordination to na(.).  

PubMed

Unprecedented homoleptic octathioether macrocyclic coordination to Na(+) in [Na([24]aneS8)](+) has been achieved by using Na[B{3,5-(CF3)2-C6H3}4] as a source of "naked" Na(+) ions and confirmed crystallographically, with d(Na-S) = 2.9561(15)-3.0524(15) Å. Density functional theory calculations show that there is electron transfer from the S 3p and C 2p valence orbitals of the ligand to the 3s and 3p orbitals of the Na(+) ion upon complexation. PMID:25723901

Champion, Martin J D; Dyke, John M; Levason, William; Light, Mark E; Pugh, David; Bhakhoa, Hanusha; Rhyman, Lydia; Ramasami, Ponnadurai; Reid, Gillian

2015-03-16

169

Effects of non-uniform root zone salinity on water use, Na+ recirculation, and Na+ and H+ flux in cotton  

PubMed Central

A new split-root system was established through grafting to study cotton response to non-uniform salinity. Each root half was treated with either uniform (100/100?mM) or non-uniform NaCl concentrations (0/200 and 50/150?mM). In contrast to uniform control, non-uniform salinity treatment improved plant growth and water use, with more water absorbed from the non- and low salinity side. Non-uniform treatments decreased Na+ concentrations in leaves. The [Na+] in the ‘0’ side roots of the 0/200 treatment was significantly higher than that in either side of the 0/0 control, but greatly decreased when the ‘0’ side phloem was girdled, suggesting that the increased [Na+] in the ‘0’ side roots was possibly due to transportation of foliar Na+ to roots through phloem. Plants under non-uniform salinity extruded more Na+ from the root than those under uniform salinity. Root Na+ efflux in the low salinity side was greatly enhanced by the higher salinity side. NaCl-induced Na+ efflux and H+ influx were inhibited by amiloride and sodium orthovanadate, suggesting that root Na+ extrusion was probably due to active Na+/H+ antiport across the plasma membrane. Improved plant growth under non-uniform salinity was thus attributed to increased water use, reduced leaf Na+ concentration, transport of excessive foliar Na+ to the low salinity side, and enhanced Na+ efflux from the low salinity root. PMID:22200663

Kong, Xiangqiang; Luo, Zhen; Dong, Hezhong; Eneji, A. Egrinya

2012-01-01

170

Kinetics of Na(+)-dependent conformational changes of rabbit kidney Na+,K(+)-ATPase.  

PubMed Central

The kinetics of Na(+)-dependent partial reactions of the Na+,K(+)-ATPase from rabbit kidney were investigated via the stopped-flow technique, using the fluorescent labels N-(4-sulfobutyl)-4-(4-(p-(dipentylamino)phenyl)butadienyl)py ridinium inner salt (RH421) and 5-iodoacetamidofluorescein (5-IAF). When covalently labeled 5-IAF enzyme is mixed with ATP, the two labels give almost identical kinetic responses. Under the chosen experimental conditions two exponential time functions are necessary to fit the data. The dominant fast phase, 1/tau 1 approximately 155 s-1 for 5-IAF-labeled enzyme and 1/tau 1 approximately 200 s-1 for native enzyme (saturating [ATP] and [Na+], pH 7.4 and 24 degrees C), is attributed to phosphorylation of the enzyme and a subsequent conformational change (E1ATP(Na+)3-->E2P(Na+)3 + ADP). The smaller amplitude slow phase, 1/tau 2 = 30-45 s-1, is attributed to the relaxation of the dephosphorylation/rephosphorylation equilibrium in the absence of K+ ions (E2P<==>E2). The Na+ concentration dependence of 1/tau 1 showed half-saturation at a Na+ concentration of 6-8 mM, with positive cooperatively involved in the occupation of the Na+ binding sites. The apparent dissociation constant of the high-affinity ATP-binding site determined from the ATP concentration dependence of 1/tau 1 was 8.0 (+/- 0.7) microM. It was found that P3-1-(2-nitrophenyl)ethyl ATP, tripropylammonium salt (NPE-caged ATP), at concentrations in the hundreds of micromolar range, significantly decreases the value of 1/tau 1, observed. This, as well as the biexponential nature of the kinetic traces, can account for previously reported discrepancies in the rates of the reactions investigated. PMID:9726935

Clarke, R J; Kane, D J; Apell, H J; Roudna, M; Bamberg, E

1998-01-01

171

Integrated surveillance of pulmonary tuberculosis and paragonimiasis in Zamboanga del Norte, the Philippines  

PubMed Central

Background Pulmonary tuberculosis (PTB) and paragonimiasis remain as health problems in certain areas in the Philippines. Both share similar clinical manifestations, which include chronic productive cough, hemoptysis, dyspnea, fever, weight loss, and night sweats. This study aimed to determine the prevalence of PTB, paragonimiasis, and co-infections in Zamboanga del Norte, Philippines. Methods This study was conducted in selected villages in two municipalities in Zamboanga del Norte. Patients with chronic cough were interviewed, examined, and requested to submit two sputum samples which were processed using Ziehl–Neelsen method to detect acid-fast bacilli (AFB), and NaOH concentration technique for the detection of Paragonimus ova. Results A total of 836 patients submitted sputum samples for examination. Prevalence was 6.7% (2.5–12.7%) for paragonimiasis and 1.9% (0.9–6.3%) for PTB. Co-infection rate was 0.3%, with two identified cases. Positivity rates for males and females were 9.6 and 5.8% for paragonimiasis and 3.4 and 1.2% for PTB. Conclusion Pulmonary tuberculosis and paragonimiasis are co-endemic in Zamboanga del Norte, suggesting the need to integrate surveillance and control efforts. Strengthening local health systems through collaboration between different sectors is recommended for effective disease control. Development of more sensitive diagnostic tests is important for more accurate disease surveillance. PMID:24601907

Belizario, Vicente; Totanes, Francis Isidore; Asuncion, Camille Ann; Leon, Winifreda De; Jorge, Manuel; Ang, Concepcion; Naig, June Rose

2014-01-01

172

Na/beta-alumina/NaAlCl4, Cl2/C circulating cell  

NASA Technical Reports Server (NTRS)

A study was made of a high specific energy battery based on a sodium negative electrode and a chlorine positive electrode with molten AlCl3-NaCl electrolyte and a solid beta alumina separator. The basic performance of a Na beta-alumina NaAlCl4, Cl2/C circulating cell at 200 C was demonstrated. This cell can be started at 150 C. The use of melting sodium chloroaluminate electrolyte overcomes some of the material problems associated with the high working temperatures of present molten salt systems, such as Na/S and LiAl/FeS, and retains the advantages of high energy density and relatively efficient electrode processes. Preliminary investigations were conducted on a sodium-chlorine static cell, material compability, electrode design, wetting, and theoretical calculations to assure a better chance of success before assembling a Na/Cl2 circulating cell. Mathematical models provide a theoretical explanation for the performance of the NaCl2 battery. The results of mathematical models match the experimental results very well. According to the result of the mathematical modeling, an output at 180 mA/sq cm and 3.2 V can be obtained with optimized cell design.

Cherng, Jing-Yih; Bennion, Douglas N.

1987-01-01

173

Na Partitioning During Thermomechanical Processing of an Mg-Sn-Zn-Na Alloy  

NASA Astrophysics Data System (ADS)

Microstructural characterization was used to examine the changes that occur in an Mg-6Sn-5Zn-0.3Na alloy from casting to extrusion at either 623 K or 723 K (350 °C or 450 °C) followed by artificial aging at 473 K (200 °C). In particular, the partitioning of Na was examined at each step using STEM-EDS mapping. Na atoms were found to preferentially partition to the Mg-Zn phase when present. After extrusion, when no Mg-Zn was observed, the spherical Mg2Sn particles were found to be enriched in Na, particularly at the higher extrusion temperature. Artificial aging following extrusion resulted in a change in Na partitioning, and a coarse distribution of Mg-Zn precipitate rods. Na microadditions led to a high as-extruded hardness, but a significant tension-compression yield asymmetry was still observed at room temperature. The compressive yield strength was found to decrease significantly after 1000 hours of aging.

TerBush, Jessica R.; Stanford, Nicole; Nie, Jian-Feng; Barnett, Matthew R.

2013-11-01

174

Conduction of Na+ and K+ through the NaK channel: molecular and Brownian dynamics studies.  

PubMed

Conduction of ions through the NaK channel, with M0 helix removed, was studied using both Brownian dynamics and molecular dynamics. Brownian dynamics simulations predict that the truncated NaK has approximately a third of the conductance of the related KcsA K+ channel, is outwardly rectifying, and has a Michaelis-Menten current-concentration relationship. Current magnitude increases when the glutamine residue located near the intracellular gate is replaced with a glutamate residue. The channel is blocked by extracellular Ca2+. Molecular dynamics simulations show that, under the influence of a strong applied potential, both Na+ and K+ move across the selectivity filter, although conduction rates for Na+ ions are somewhat lower. The mechanism of conduction of Na+ differs significantly from that of K+ in that Na+ is preferentially coordinated by single planes of pore-lining carbonyl oxygens, instead of two planes as in the usual K+ binding sites. The water-containing filter pocket resulting from a single change in the selectivity filter sequence (compared to potassium channels) disrupts several of the planes of carbonyl oxygens, and thus reduces the filter's ability to discriminate against sodium. PMID:18456826

Vora, Taira; Bisset, David; Chung, Shin-Ho

2008-08-01

175

Computational interpretation of 23Na MQMAS NMR spectra: A comprehensive investigation of the Na environment in silicate glasses  

NASA Astrophysics Data System (ADS)

Molecular dynamics, density functional theory calculations and 23Na NMR experiments have been used to inspect the chemical and structural characteristics of the Na environment in soda-lime silicate (CSN) and aluminosilicate (CASN) glasses. The use of an improved 3QMAS pulse sequence has allowed a clear identification of different Na sites. Average coordination numbers have been extracted by fitting the 23Na 3QMAS spectra with the computed NMR parameters. The results show that the 23Na ?iso values correlate with the average <Na-O> distances only when the different coordination numbers are explicitly taken into account.

Gambuzzi, Elisa; Charpentier, Thibault; Menziani, Maria Cristina; Pedone, Alfonso

2014-09-01

176

The Human Phospholamban Arg14-Deletion Mutant Localizes to Plasma Membrane and Interacts with the Na/K-ATPase  

PubMed Central

Depressed Ca-handling in cardiomyocytes is frequently attributed to impaired sarcoplasmic reticulum (SR) function in human and experimental heart failure. Phospholamban (PLN) is a key regulator of SR and cardiac function, and PLN mutations in humans have been associated with dilated cardiomyopathy (DCM). We previously reported the deletion of the highly conserved amino acid residue arginine 14 (nucleic acids 39, 40 and 41) in DCM patients. This basic amino acid is important in maintaining the upstream consensus sequence for PKA phosphorylation of Ser 16 in PLN. To assess the function of this mutant PLN, we introduced the PLN-R14Del in cardiac myocytes of the PLN null mouse. Transgenic lines expressing mutant PLN-R14Del at similar protein levels to wild types exhibited no inhibition of the initial rates of oxalate-facilitated SR Ca uptake compared to PLN-knockouts (PLN-KO). The contractile parameters and Ca-kinetics also remained highly stimulated in PLN-R14Del cardiomyocytes, similar to PLN-KO, and isoproterenol did not further stimulate these hyper-contractile basal parameters. Consistent with the lack of inhibition on SR Ca-transport and contractility, confocal microscopy indicated that the PLN-R14Del failed to co-localize with SERCA2a. Moreover, PLN-R14Del did not co-immunoprecipitate with SERCA2a (as did WT-PLN), but rather co-immunoprecipitated with the sarcolemmal Na/K-ATPase (NKA) and stimulated NKA activity. In addition, studies in HEK cells indicated significant fluorescence resonance energy transfer between PLN-R14Del-YFP and NKA?1-CFP, but not with the NKA regulator phospholemman. Despite the enhanced cardiac function in PLN-R14Del hearts (as in PLN-knockouts), there was cardiac hypertrophy (unlike PLN-KO) coupled with activation of Akt and the MAPK pathways. Thus, human PLN-R14Del is misrouted to the sarcolemma, in the absence of endogenous PLN, and alters NKA activity, leading to cardiac remodeling. PMID:22155237

Haghighi, Kobra; Pritchard, Tracy; Bossuyt, Julie; Waggoner, Jason R.; Yuan, Qunying; Fan, Guo-Chang; Osinska, Hanna; Anjak, Ahmad; Rubinstein, Jack; Robbins, Jeffrey; Bers, Donald M.; Kranias, Evangelia G.

2012-01-01

177

Los orígenes del Partido del Socialismo Democrático (1989-1993): el ave fénix roja en Alemania  

Microsoft Academic Search

El Partido del Socialismo Democrático (Partei des Demokratischen Sozialismus), surgido de la descomposición interna del SED (Sozialistiscbe Einbeitspartei Deutschlands), es un caso relevante de adaptación de los partidos únicos en los regímenes comunistas a la democracia plurípar-tidista. Dadas las peculiaridades de la transición en la República Democrática de Alemania, acelerada por su rápida integración en la República Federal, el SED

Ricardo Martín de la Guardia

2005-01-01

178

Simulación numérica del transporte del herbicida glifosato en la zona no saturada  

Microsoft Academic Search

RESUMEN. La simulación numérica junto con los experimentos de campo constituyen herramientas imprescindibles para el estudio del transporte de agua y de sustancias contaminantes en el subsuelo. El objetivo de este trabajo es presentar un modelo numérico para describir la migración de un contaminante sometido a procesos de adsorción y de degradación en la zona no saturada (ZNS) del terreno.

L. Guarracino; L. Candela Lledó; J. E. Santos

1999-01-01

179

Serie de Derecho Económico 1. Casos de estudio de aplicación del Análisis Económico del Derecho  

Microsoft Academic Search

El interés por el estudio del Análisis Económico del Derecho –AED– no es nuevo. En su versión clásica, que corresponde a la Escuela de Chicago, y también en las versiones más recientes como la nueva economía institucional, el AED resulta ser una herramienta útil para estudiar problemas jurídicos, la forma de incidir de la regulación en el desarrollo y en

Varios

180

Preguntas y respuestas acerca del Estudio del Tamoxifeno y Raloxifeno (STAR)  

Cancer.gov

El Estudio del Tamoxifeno y Raloxifeno (STAR, por sus siglas en inglés) es un estudio clínico (un estudio de investigación conducido con voluntarios) diseñado para ver cómo el medicamento raloxifeno (Evista®) se compara con el medicamento tamoxifeno (Nolvadex®) en reducir la incidencia de cáncer del seno en las mujeres con alto riesgo de desarrollar la enfermedad.

181

Experiencias en la incorporación del enfoque poblacional en la planeación del desarrollo territorial. Memorias  

Microsoft Academic Search

Este documento contiene las ponencias presentadas durante el Encuentro Experiencias en la incorporación del enfoque poblacional en la planeación del desarrollo territorial realizado en Bogotá los días 6 y 7 de noviembre de 2008 en la Universidad Externado de Colombia. El evento fue organizado por el Fondo de Población de las Naciones Unidas -UNFPA-, el Departamento Nacional de Planeación -DNP-,

Yolanda Bodnar Contreras

182

VI CONGRESO DEL CEISAL Toulouse, del 30 de junio al 3 de Julio de 2010  

E-print Network

-30Jun2010 #12;Identificación de fortalezas y debilidades del G8+5 ante la crisis energética 2 RESUMEN Cumbre 2008 de Ministros de Finanzas de la Mancomunidad Británica de Naciones celebrada del 6 al 8 de

Paris-Sud XI, Université de

183

Nac onal~na akadem nauk Ukra ni KONDENSOVANIH  

E-print Network

baga- tokomponentno sistemi zar d enih tverdih sfer, wo otrimane metodom ner vnova nogo statistiqnogo tiqnost na malih v dstan h. Qisel~n rozrahunki dl zsuvno v' zkost ta teploprov dnost na osnov normal~nogo

184

Intertextual Sexual Politics: Illness and Desire in Enrique Gomez Carrillo's "Del amor", "del dolor y del vicio" and Aurora Caceres's "La rosa muerta"  

ERIC Educational Resources Information Center

This study explores the intertextuality between Aurora Caceres's "La rosa muerta" (1914) and the novel "Del amor, del dolor y del vicio" (1898) by her ex-husband, Enrique Gomez Carrillo. Caceres strategically mentions Gomez Carrillo's novel in "La rosa muerta" to invite a reading of her work in dialogue with his. Both narratives follow the sexual…

LaGreca, Nancy

2012-01-01

185

Balances energéticos y uso del sueloen la agricultura catalana: una comparación entre mediados del siglo XIX y finales del siglo XX  

Microsoft Academic Search

El presente trabajo analiza y compara, desde la perspectiva analítica del metabolismo social, los usos del suelo y los balances energéticos derivados de estos usos de los sistemas agrarios de cinco municipios de la comarca catalana del Vallès, en dos momentos históricos que ilustran las características y magnitud de las transformaciones que se han producido en los sistemas agrarios catalanes

Xavier Cussó; Ramon Garrabou; José Ramon Olarieta; Enric Tello

2006-01-01

186

Rescue of na+ affinity in aspartate 928 mutants of na+,k+-ATPase by secondary mutation of glutamate 314.  

PubMed

The Na(+),K(+)-ATPase binds Na(+) at three transport sites denoted I, II, and III, of which site III is Na(+)-specific and suggested to be the first occupied in the cooperative binding process activating phosphorylation from ATP. Here we demonstrate that the asparagine substitution of the aspartate associated with site III found in patients with rapid-onset dystonia parkinsonism or alternating hemiplegia of childhood causes a dramatic reduction of Na(+) affinity in the ?1-, ?2-, and ?3-isoforms of Na(+),K(+)-ATPase, whereas other substitutions of this aspartate are much less disruptive. This is likely due to interference by the amide function of the asparagine side chain with Na(+)-coordinating residues in site III. Remarkably, the Na(+) affinity of site III aspartate to asparagine and alanine mutants is rescued by second-site mutation of a glutamate in the extracellular part of the fourth transmembrane helix, distant to site III. This gain-of-function mutation works without recovery of the lost cooperativity and selectivity of Na(+) binding and does not affect the E1-E2 conformational equilibrium or the maximum phosphorylation rate. Hence, the rescue of Na(+) affinity is likely intrinsic to the Na(+) binding pocket, and the underlying mechanism could be a tightening of Na(+) binding at Na(+) site II, possibly via movement of transmembrane helix four. The second-site mutation also improves Na(+),K(+) pump function in intact cells. Rescue of Na(+) affinity and Na(+) and K(+) transport by second-site mutation is unique in the history of Na(+),K(+)-ATPase and points to new possibilities for treatment of neurological patients carrying Na(+),K(+)-ATPase mutations. PMID:25713066

Holm, Rikke; Einholm, Anja P; Andersen, Jens P; Vilsen, Bente

2015-04-10

187

Na(2+x)Ti6O13 as potential negative electrode material for Na-ion batteries.  

PubMed

Na-ion batteries provide one of the most promising alternatives for Li-ion batteries due to the high abundance and low cost of Na. The strongly electropositive character of Na enables almost comparable cell potentials. Here we show that by lowering the cutoff voltage from 0.3 to 0 V vs Na/Na(+) the capacity of the Na2Ti6O13 negative electrode material can be enhanced from 49.5 mAh/g (Na(2+1)Ti6O13) to a promising 196 mAh/g (Na(2+4)Ti6O13) for at least 10 cycles, after which it gradually reduces. To understand the structural changes in situ X-ray diffraction is performed and compared with density functional theory calculations. A consistent picture of the evolution in lattice parameters and Na-ion positions is presented. The results show that Na-ion intercalation in the Na(2+x)Ti6O13 host structure is limited to Na(2+2)Ti6O13 and proceeds through a solid solution reaction. Only small changes in lattice parameters promote that the insertion reaction is highly reversible. Further increasing the Na composition below 0.3 V appears to lead to loss in crystallinity, which in combination with solid electrolyte interface formation is suggested to be the origin of the gradually reducing reversible capacity. PMID:25079946

Shen, Kun; Wagemaker, Marnix

2014-08-18

188

Rechargeable Na/Na0.44MnO2 cells with ionic liquid electrolytes containing various sodium solutes  

NASA Astrophysics Data System (ADS)

Orthorhombic Na0.44MnO2 with wide structural tunnels for sodium ion transport is synthesized. Butylmethylpyrrolidinium-bis(trifluoromethanesulfonyl)imide (BMP-TFSI) ionic liquid (IL) with various Na solutes, namely NaBF4, NaClO4, NaTFSI, and NaPF6, is used as an electrolyte for rechargeable Na/Na0.44MnO2 cells. The cell with NaClO4-incorporated IL electrolyte exhibits superior charge-discharge performance due to it having the lowest solid-electrolyte-interface resistance and charge transfer resistance at both the Na and Na0.44MnO2 electrodes. The IL electrolyte shows high thermal stability and is suitable for use at an elevated temperature. At 75 °C, the measured capacity of Na0.44MnO2 in the IL electrolyte with NaClO4 is as high as 115 mAh g-1 (at 0.05 C), which is close to the theoretical value (121 mAh g-1). Moreover, 85% of this capacity can be retained when the charge-discharge rate is increased to 1 C. These properties are superior to those of a conventional organic electrolyte.

Wang, Chueh-Han; Yeh, Yu-Wen; Wongittharom, Nithinai; Wang, Yi-Chen; Tseng, Chung-Jen; Lee, Sheng-Wei; Chang, Wen-Sheng; Chang, Jeng-Kuei

2015-01-01

189

Slip casting alumina with Na-CMC  

SciTech Connect

Many forming methods are in common use for engineering ceramics. Of these, slip casting is an ideal forming method because of its low cost, simplicity and flexibility, potential for uniform particle packing and suitability to the production of articles of intricate shape. Slip casting nonclay materials, such as alumina, requires the use of both a deflocculant and a binder. There are many commercially available deflocculants and binders that can be tested in alumina casting slips. However, determination of a suitable deflocculant/binder combination and quantification of the optimal additions of the deflocculant/binder pair can be time consuming. Certain deflocculants are capable of acting as binders. One such additive is sodium carboxymethylcellulose (Na-cmc), a cellulose ether. Na-cmc is a powerful binder. It is a member of the carbohydrate binder group--the binder group with the strongest binding power. It is capable of acting as a deflocculant in glazes and nonclay casting slips.

Ruys, A.J.; Sorrell, C.C. [Univ. of New South Wales, Sydney, New South Wales (Australia)

1996-11-01

190

Rat hepatocytes exhibit basolateral Na+\\/HCOâ- cotransport  

Microsoft Academic Search

Primary cultures and plasma membrane vesicles were used to characterize Na+ and HCO3- transport by rat hepatocytes. Na+ uptake into hepatocytes was stimulated approximately 10-fold by 25 mM extracellular HCO3-.HCO3--stimulated Na+ uptake was saturable, abolished by 4-acetamido-4'-isothiocyano-2,2'-disulfonic acid stilbene (SITS), and unaffected by amiloride or Cl- removal. Neither propionate nor acetate reproduced this effect of HCO3-. 22Na efflux from preloaded

E. L. Renner; J. R. Lake; B. F. Scharschmidt; B. Zimmerli; P. J. Meier

1989-01-01

191

Igneous origin for the Na in the cloud of Io  

NASA Technical Reports Server (NTRS)

Mixtures of sulfur and Na-bearing silicates were heated in evacuated silica glass capsules to temperatures between 600 C and 950 C. At or above 850 C, Na-silicate glass reacts with elemental S to form a (Na, K) sulfide. Mobilization of this phase may account for the presence of Na and K on the surface of Io, and hence in the material sputtered onto the Jovian magnetosphere.

Johnson, Mary L.; Burnett, D. S.

1990-01-01

192

Transport of Na + inside the giant axon of squid  

Microsoft Academic Search

The transport mechanism of Na ions within the nerve cell was studied by measuring the radioactivity distribution profile of22Na that had been intracellularly injected into the giant axon. Specifically, we tested whether or not the movement of Na ions\\u000a is coupled with the process of “fast axonal transport.” Results of our measurements indicate that the intracellular transport\\u000a of Na+ and

Donald C. Chang

1985-01-01

193

Pojem nekone#na pou##vaj# matematici t#m## odjak#iva. Vzpome#me nap#. na Z#n#na (asi 480 --430) a jeho #lohu o Achillovi a #elv#, #i na #vahy #ek# o tom, #e  

E-print Network

D#L I. Pojem nekone#na pou##vaj# matematici t#m## odjak#iva. Vzpome#me nap#. na Z#n#na (asi 480#jak# #innosti #i vlastnosti (tzv. potenci#ln# forma nekone#na) --- nap#. #Achilles #elvu nikdy nedohon##, #po#my t#kaj#c# se zna#n# slo#it#ch ##st# re#ln# p##mky, nap#. p#i vy#et#ov#n# defini#n#ch obor# funkc

Stanovsky, David

194

The Rapid-onset Dystonia Parkinsonism Mutation D923N of the Na+,K+-ATPase ?3 Isoform Disrupts Na+ Interaction at the Third Na+ Site*  

PubMed Central

Rapid-onset dystonia parkinsonism (RDP), a rare neurological disorder, is caused by mutation of the neuron-specific ?3-isoform of Na+,K+-ATPase. Here, we present the functional consequences of RDP mutation D923N. Relative to the wild type, the mutant exhibits a remarkable ?200-fold reduction of Na+ affinity for activation of phosphorylation from ATP, reflecting a defective interaction of the E1 form with intracellular Na+. This is the largest effect on Na+ affinity reported so far for any Na+,K+-ATPase mutant. D923N also affects the interaction with extracellular Na+ normally driving the E1P to E2P conformational transition backward. However, no impairment of K+ binding was observed for D923N, leading to the conclusion that Asp923 is specifically associated with the third Na+ site that is selective toward Na+. The crystal structure of the Na+,K+-ATPase in E2 form shows that Asp923 is located in the cytoplasmic half of transmembrane helix M8 inside a putative transport channel, which is lined by residues from the transmembrane helices M5, M7, M8, and M10 and capped by the C terminus, recently found involved in recognition of the third Na+ ion. Structural modeling of the E1 form of Na+,K+-ATPase based on the Ca2+-ATPase crystal structure is consistent with the hypothesis that Asp923 contributes to a site binding the third Na+ ion. These results in conjunction with our previous findings with other RDP mutants suggest that a selective defect in the handling of Na+ may be a general feature of the RDP disorder. PMID:20576601

Einholm, Anja Pernille; Toustrup-Jensen, Mads S.; Holm, Rikke; Andersen, Jens Peter; Vilsen, Bente

2010-01-01

195

Sources of Na for the Io atmosphere  

NASA Technical Reports Server (NTRS)

The physics and geology of Io have been extensively studied, but there has been little discussion of the chemistry. Relatively little is known about Io chemistry, but there are constraints. Further, it will be a long time before improvements will result from direct observation, given the severe difficulties with the Galileo mission. Via laboratory simulation experiments, plausible thermochemical and photochemical processes which determine the nature and amounts of surface constituents of Io are explored. The well-known density of Io shows that the planet overall is rocky. Because the orbit of Io is well within the magnetosphere of Jupiter and because Io only has a thin, transient SO2 atmosphere, the surface is continually sputtered with magnetospheric ions. Complex processes ionize and accelerate the Io surface atoms to keV and MeV energies. Remarkably, only S, O, and Na ions were found by Voyager. Sputtering also produces an atomic cloud of Na and S (O not observable) with a trace of K. Both gaseous and solid SO2 are known from spectroscopic studies. A trace of H2S and possibly CO2 are present. Geologic features are interpreted in terms of elemental S, but there is no direct evidence for this constituent. We thus have a rocky planet which does not have rocks on the surface. Our general goal is to understand the cycling of Na, S, and O through the crust and atmosphere on present-day Io and to understand how Io evolved to this state. A specific objective was to determine the phases on the surface which are the source of the Na in the atmosphere of Io.

Burnett, D. S.; Ellis, Susan B.; Rice, A.; Epstein, S.

1993-01-01

196

Matter radii of Na and Mg isotopes  

Microsoft Academic Search

The interaction cross sections (?I) of ANa (A = 20–23, 25–32) and AMg (A = 20, 22–25, 27, 29–33) on carbon target have been measured at a beam energy of around 950 A MeV. The effective root-mean-square matter radii of these isotopes were deduced from ?I by a Glauber-type calculation. Combining the isotope-shift data with the present Na data the

T. Suzuki; H. Geissel; O. Bochkarev; L. Chulkov; M. Golovkov; D. Hirata; H. Irnich; Z. Janas; H. Keller; T. Kobayashi; G. Kraus; G. Muenzenberg; S. Neumaier; F. Nickel; A. Ozawa; A. Piechaczeck; E. Roeckl; W. Schwab; K. Suemmerer; K. Yoshida; I. Tanihata

1997-01-01

197

The Na + \\/I ? Symporter (NIS): Recent Advances  

Microsoft Academic Search

The Na+\\/I- symporter (NIS) catalyzes the accumulation of iodide into thyroid cells, an essential step in the biosynthesis of thyroid hormones. As a result of the isolation of the rat NIS cDNA, steadfast advances in the study of NIS at the molecular level have resulted in the following accomplishments: generation of high-affinity anti-NIS antibodies, elucidation of NIS stoichiometry and specificity

Orlie Levy; Antonio De la Vieja; Nancy Carrasco

1998-01-01

198

Influence of Salt Purity on Na+ and Palmitic Acid Interactions  

E-print Network

Influence of Salt Purity on Na+ and Palmitic Acid Interactions Zishuai Huang, Wei Hua, Dominique of salt purity on the interactions between Na+ ions and the carboxylate (COO- ) head group of palmitic frequency generation (VSFG) spectroscopy. Ultrapure (UP) and ACS grade NaCl salts are used for aqueous

199

Electrochemical Properties of Monoclinic NaNiO2  

E-print Network

Monoclinic NaNiO[subscript 2] is re-investigated as a positive electrode material for sodium ion batteries. We observe reversible Na extraction and insertion of about 120 mAh/g when NaNiO[subscript 2] is cycled between ...

Vassilaras, Plousia E.

200

Reich e a possibilidade do bem-estar na cultura  

Microsoft Academic Search

Numa entrevista dada em 1952, Reich afirmou que o texto freudiano O mal-estar na cultura fora escrito em resposta a uma conferência que proferira na casa do Fre ud sobre o tema profilaxia das neuroses. Inspirado nesse depoimento, este trabalho procura investigar as teses reichianas que se contrapõem ao pensamento freudiano de O mal -estar na cultura. Diferenciam-se as posições

Paulo Albertini

2003-01-01

201

Route, mechanism, and implications of proton import during Na+/K+ exchange by native Na+/K+-ATPase pumps  

PubMed Central

A single Na+/K+-ATPase pumps three Na+ outwards and two K+ inwards by alternately exposing ion-binding sites to opposite sides of the membrane in a conformational sequence coupled to pump autophosphorylation from ATP and auto-dephosphorylation. The larger flow of Na+ than K+ generates outward current across the cell membrane. Less well understood is the ability of Na+/K+ pumps to generate an inward current of protons. Originally noted in pumps deprived of external K+ and Na+ ions, as inward current at negative membrane potentials that becomes amplified when external pH is lowered, this proton current is generally viewed as an artifact of those unnatural conditions. We demonstrate here that this inward current also flows at physiological K+ and Na+ concentrations. We show that protons exploit ready reversibility of conformational changes associated with extracellular Na+ release from phosphorylated Na+/K+ pumps. Reversal of a subset of these transitions allows an extracellular proton to bind an acidic side chain and to be subsequently released to the cytoplasm. This back-step of phosphorylated Na+/K+ pumps that enables proton import is not required for completion of the 3 Na+/2 K+ transport cycle. However, the back-step occurs readily during Na+/K+ transport when external K+ ion binding and occlusion are delayed, and it occurs more frequently when lowered extracellular pH raises the probability of protonation of the externally accessible carboxylate side chain. The proton route passes through the Na+-selective binding site III and is distinct from the principal pathway traversed by the majority of transported Na+ and K+ ions that passes through binding site II. The inferred occurrence of Na+/K+ exchange and H+ import during the same conformational cycle of a single molecule identifies the Na+/K+ pump as a hybrid transporter. Whether Na+/K+ pump–mediated proton inflow may have any physiological or pathophysiological significance remains to be clarified. PMID:24688018

Vedovato, Natascia

2014-01-01

202

Comparative studies of etching mechanisms of CR-39 in NaOH/H2O and NaOH/ethanol  

E-print Network

Comparative studies of etching mechanisms of CR-39 in NaOH/H2O and NaOH/ethanol K.C.C. Tse, D Avenue, Kowloon Tong, Hong Kong Available online 13 May 2007 Abstract The bulk etch rate for CR-39 in NaOH/ethanol accumulates on the surface of CR-39 detector during etching in NaOH/ethanol, which is absent during etching

Yu, K.N.

203

Digitalización de diapositivas del Sol en H ?  

NASA Astrophysics Data System (ADS)

El objetivo de este trabajo ha sido el de obtener imágenes digitalizadas de las diapositivas tomadas del Sol en luz de hidrógeno de la línea correspondiente a H?, y de esta manera llegar a convertir las mismas a un archivo digital para poder ser tratadas luego por computadora y poder contabilizar con exactitud, mediante un programa adecuado para tal fin, las zonas activas del Sol en la imagen digitalizada. En principio, para llegar a esto se pensó en la utilización de medios accesibles, y como detector se utilizó un fototransistor ubicado dentro de un soporte rectangular sobre dos ejes de desplazamiento X e Y. Se han obtenido con este procedimiento imágenes de buena calidad, construídas a partir de tres datos digitalizados en cada barrido que aportan la posición X e Y y la intensidad del pixel en ese punto indicada en 255 tonos de grises.

Missio, H.; Montenegro, C.; Montenegro, R.

204

Na insertion mechanisms in vanadium oxide nanotubes for na-ion batteries.  

PubMed

In this study, we successfully synthesized lamellar-structured Ni0.1VOx NTs by a microwave-assisted hydrothermal method and cation exchange reaction. High initial discharge capacity and 100% efficiency were obtained when the Ni0.1VOx NTs cathode was used as a cathode material for the Na battery. The intercalation mechanism and capacity fading effect were investigated in detail both experimentally using Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) analyses and theoretically using the ab initio simulation method. During the intercalation of Na(+) into VOx NT structures, TEM, XRD, FT-IR, and XPS data revealed the cointercalation of the solvent, resulting in the expansion of the interlayer spacing and carbon and oxygen adsorption. The experimental and simulation results suggest that solvent molecules coordinated the Na insertion mechanisms into the amine interlayer during discharging. These understandings of the Na intercalation mechanism in materials based on Ni0.1VOx NTs would be useful to design more stable and high-performance VOx-based electrodes for Na battery applications. PMID:25562784

Kim, Hyunjin; Kim, Dong Young; Kim, Yongsu; Lee, Seok-Soo; Park, Kwangjin

2015-01-28

205

Interaction of (Na + K + 2 Cl) cotransport and the Na/K pump in cultured chick cardiac myocytes.  

PubMed

We have recently reported the presence of an electroneutral (Na + K + 2 Cl) cotransport mechanism that is bumetanide-sensitive and maintains Cli above its electrochemical equilibrium in cultured chick heart cells. In steady state, (Na + K + 2 Cl) cotransport is inwardly directed and so contributes to the Na influx that must be counterbalanced by the activity of the Na/K pump to maintain Nai homeostasis. We now show that manipulating (Na + K + 2 Cl) cotransport by restoring Clo to a Cl-free solution indirectly influences Na/K pump activity because the bumetanide-sensitive recovery of aiNa to its control level and the accompanying hyperpolarization could be blocked by 10(-4)M ouabain. In another protocol, when the Na/K pump was reactivated by restoring Ko (from 0.5 mM to 5.4 mM) and removing ouabain, the recovery of aNa was attenuated by 10(-4)M bumetanide. The relatively slow rate of ouabain dissociation coupled with the activation of Na influx by (Na + K + 2 Cl) cotransport clearly establishes the interaction of these transport mechanisms in regulating Nai. Although (Na + K + 2 Cl) cotransport is electroneutral, secondary consequences of its activity can indirectly affect the electrophysiological properties of cardiac cells. PMID:2811863

Liu, S; Jacob, R; Piwnica-Worms, D; Lieberman, M

1989-09-01

206

Na(+) channel function, regulation, structure, trafficking and sequestration.  

PubMed

This paper is the second of a series of three reviews published in this issue resulting from the University of California Davis Cardiovascular Symposium 2014: Systems approach to understanding cardiac excitation-contraction coupling and arrhythmias: Na(+) channel and Na(+) transport. The goal of the symposium was to bring together experts in the field to discuss points of consensus and controversy on the topic of sodium in the heart. The present review focuses on Na(+) channel function and regulation, Na(+) channel structure and function, and Na(+) channel trafficking, sequestration and complexing. PMID:25772290

Chen-Izu, Ye; Shaw, Robin M; Pitt, Geoffrey S; Yarov-Yarovoy, Vladimir; Sack, Jon T; Abriel, Hugues; Aldrich, Richard W; Belardinelli, Luiz; Cannell, Mark B; Catterall, William A; Chazin, Walter J; Chiamvimonvat, Nipavan; Deschenes, Isabelle; Grandi, Eleonora; Hund, Thomas J; Izu, Leighton T; Maier, Lars S; Maltsev, Victor A; Marionneau, Celine; Mohler, Peter J; Rajamani, Sridharan; Rasmusson, Randall L; Sobie, Eric A; Clancy, Colleen E; Bers, Donald M

2015-03-15

207

Acidosis Differentially Modulates Inactivation in NaV1.2, NaV1.4, and NaV1.5 Channels  

PubMed Central

NaV channels play a crucial role in neuronal and muscle excitability. Using whole-cell recordings we studied effects of low extracellular pH on the biophysical properties of NaV1.2, NaV1.4, and NaV1.5, expressed in cultured mammalian cells. Low pH produced different effects on different channel subtypes. Whereas NaV1.4 exhibited very low sensitivity to acidosis, primarily limited to partial block of macroscopic currents, the effects of low pH on gating in NaV1.2 and NaV1.5 were profound. In NaV1.2 low pH reduced apparent valence of steady-state fast inactivation, shifted the ?(V) to depolarizing potentials and decreased channels availability during onset to slow and use-dependent inactivation (UDI). In contrast, low pH delayed open-state inactivation in NaV1.5, right-shifted the voltage-dependence of window current, and increased channel availability during onset to slow and UDI. These results suggest that protons affect channel availability in an isoform-specific manner. A computer model incorporating these results demonstrates their effects on membrane excitability. PMID:22701426

Vilin, Yury Y.; Peters, Colin H.; Ruben, Peter C.

2012-01-01

208

Formation of Na-containing molecular ions at Io  

NASA Technical Reports Server (NTRS)

Fast sodium atoms, which appear to be associated with the motion of the magnetic 'field lines' downstream from Io (Schneider et al. 1991), are thought to be produced by dissociation of NaX(+) in Io's plasma torus. It was suggested that these molecular ions are formed near Io's exobase by electron-impact ionization and picked up be the corotating filed lines (Wilson and Schneider 1994). Because electron cooling processes dominate electron-impact ionization in Io's corona, two reactions are suggested here as sources of NaX(+) and, hence, as the ultimate sources of the observed fast Na. First, the charge-exchange cross sections for forming NaX(+) are shown to be large for plasma torus ions (O(+), S(+), O(2+), S(3+)) colliding with NaX molecules in Io's corona. Sputtering from the surface (Chrisey et al. 1988) and rapid transport to the exobase is a potential source of NaX, where X is O,S, Na, or a molecular species such as NaS or O2. Second ions of the more abundant molecules (e.g., SO(+), SO2(+), O2(+), and S2(+)) can react efficiently with atomic Na in Io's corona to form NaX(+). Here cross sections are estimated for these two processes, as well as for charge exchange in O(+) and S(+) on Na collisions.

Johnson, R. E.

1994-01-01

209

Na+-pyrophosphatase: a novel primary sodium pump.  

PubMed

Membrane-bound pyrophosphatase (PPase) is commonly believed to couple pyrophosphate (PPi) hydrolysis to H+ transport across the membrane. Here, we demonstrate that two newly isolated bacterial membrane PPases from the mesophile Methanosarcina mazei (Mm-PPase) and the moderate thermophile Moorella thermoacetica and a previously described PPase from the hyperthermophilic bacterium Thermotoga maritima catalyze Na+ rather than H+ transport into Escherichia coli inner membrane vesicles (IMV). When assayed in uncoupled IMV, the three PPases exhibit an absolute requirement for Na+ but display the highest hydrolyzing activity in the presence of both Na+ and K+. Steady-state kinetic analysis of PPi hydrolysis by Mm-PPase revealed two Na+ binding sites. One of these sites can also bind K+, resulting in a 10-fold increase in the affinity of the other site for Na+ and a 2-fold increase in maximal velocity. PPi-driven 22Na+ transport into IMV containing Mm-PPase was unaffected by the protonophore carbonyl cyanide m-chlorophenylhydrazone, inhibited by the Na+ ionophore monensin, and activated by the K+ ionophore valinomycin. The Na+ transport was accompanied by the generation of a positive inside membrane potential as reported by Oxonol VI. These findings define Na+-dependent PPases as electrogenic Na+ pumps. Phylogenetic analysis suggests that ancient gene duplication preceded the split of Na+- and H+-PPases. PMID:17605473

Malinen, Anssi M; Belogurov, Georgiy A; Baykov, Alexander A; Lahti, Reijo

2007-07-31

210

Weekday Blue/Orange Route PAX/hr. PAX/mi. $/Pass. Weekend Blue/Orange Route n/a n/a n/a Weekday Blue/Orange Route  

E-print Network

/a n/a n/a Grounds Loop Weekend Hereford Special 21.03 2.23 $0.96 Central Grounds Shuttle Holiday Blue/Orange Route n/a n/a n/a Weekend Hereford Special Holiday Special 30.07 3.11 $0.69 Holiday Blue/Orange Route 9

Acton, Scott

211

Pair correlations in an NaCl-SPC water model  

NASA Astrophysics Data System (ADS)

The ten pair correlation functions characterizing the equilibrium structure of a simple electrolyte such as NaCl-water and previously obtained for a NaCl-SPC water model within the extended RISM framework are tested against molecular dynamics, constrained dynamics and Monte Carlo simulations employing Ewald and reaction field schemes for a high-temperature, highpressure thermodynamic state where all these approaches become simultaneously feasible. The O-O, H-H, Cl-O, and Na-Na RISM correlations are in good agreement with the simulation data. The Na-O, Na-H, and Na-Cl results agree in phase, but the RISM peaks are too small. Distinct differences in the position of the first peak are observed in the case of the O-H, Cl-H, and Cl-Cl pair correlations. These results provide evidence that the main reason for these discrepancies are the statistical approximations involved in the extended RISM scheme.

Hummer, Gerhard; Soumpasis, Dikeos M.; Neumann, Martin

212

Diffuse sorption modeling: apparent H/Na, or the same, Al/Na exchange on clays.  

PubMed

Clay minerals are specified by permanent negative surface charge. In solutions of sodium salts, the surface of clay is covered by exchangeable sodium ions. In an acidic field (pH<4-6), sodium ions are displaced from the surface. This apparent H/Na exchange is conditioned by dissolution of alumina, followed by Al/Na exchange. Two kinds of published experimental data were considered in order to follow Al/Na exchange: the first is direct measurement of exchangeable sodium and aluminum in clay, and the second is exchange sorption of trace metal. Because of the equivalency of ionic exchange, trace metal acts as a probe, indicating the sodium content in clay. These experimental data were successfully modeled with use of the Poisson-Boltzmann equation, with the assumption that all exchange cations are located in the diffuse layer. PMID:19464695

Pivovarov, Sergey

2009-08-15

213

Difference between hypertonic NaCl and NaHCO3 as osmotic diuretics in dog kidneys.  

PubMed

To compare the osmotic inhibitory effects of NaCl and NaHCO3 on proximal tubular fluid reabsorption, plasma osmolality was raised by 40 mosmol kg-1 H2O by infusing hypertonic NaCl and NaHCO3 in volume-expanded dogs receiving ethacrynic acid. In five dogs studied at constant plasma pH 7.5, both NaCl and NaHCO3 reduced water reabsorption by 29 +/- 2%. However, NaCl infusion reduced bicarbonate reabsorption by 31 +/- 2%, whereas bicarbonate reabsorption remained unchanged during NaHCO3 infusion. In six dogs, bicarbonate reabsorption was kept constant during NaCl and NaHCO3 infusion by adjustments of plasma pH. At similar glomerular filtration rates (42.4 +/- 2.9 ml min-1), water reabsorption was 28.7 +/- 1.7 ml min-1 in the control period, 29.4 +/- 2.5 ml min-1 during hypertonic NaCl infusion and 20.6 +/- 1.2 ml min-1 during hypertonic NaHCO3 infusion. Therefore, NaCl did not reduce proximal tubular water reabsorption by a direct osmotic effect. By calculating the regression coefficient for the relationship between measured chloride reabsorption and maximal convective chloride flux, the effective reflection coefficient for NaCl averaged 0.11 +/- 0.01. The combination of a low reflection coefficient and high permeability may explain why hypertonic NaCl is not an osmotic diuretic. PMID:2618758

Ostensen, J; Stokke, E S; Bugge, J F; Langberg, H; Kiil, F

1989-10-01

214

Student Competition: Siting Potential Dams at Camp Del Webb, Utah  

E-print Network

Siting Potential Dams at Camp Del Webb, Utah Presented By: Kyle Wamser Problem ? Camp Del Webb is Lacking an Onsite Lake ? High Adventure Bases generally need aquatics ? Large lake nearby, but transportation is required ? Possible Solution...

Wamser, William Kyle

2007-11-14

215

Polo Universitario Imperiese Scienze del turismo: impresa, cultura e territorio  

E-print Network

-PSI/01 Psicologia del turismo (mod. 1 con M-PSI/01) 6 caratterizzante BIO/08 Antropologia per il turismo (mod. 2 con BIO/08) 6 affini SPS/07 Sociologia del turismo 9 caratterizzante L-ART/05 Antropologia

Robbiano, Lorenzo

216

Transformación de los programas de estudios clínicos del NCI  

Cancer.gov

Información sobre los programas e iniciativas del NCI que patrocinan, realizan, crean o apoyan estudios clínicos, entre los que se incluyen la Red Nacional de Estudios Clínicos (NCTN) y el Programa de Investigación Oncológica Comunitaria (NCORP) del NCI.

217

Centro para la Salud Mundial (CGH) del NCI  

Cancer.gov

El Centro para la Salud Mundial (CGH) del Instituto Nacional del Cáncer coordina actividades de investigación y trabaja con socios nacionales e internacionales para comprender y enfrentar la carga que representa el cáncer a nivel mundial.

218

La reconstrucción del seno después de una mastectomía  

Cancer.gov

Hoja informativa que describe la reconstrucción del seno (mama) después de una mastectomía. Contiene información sobre las opciones quirúrgicas, los cuidados de seguimiento y los exámenes de detección del cáncer de seno después de la reconstrucción.

219

Gas-exposure enhanced Na* emission from Na-rich surfaces  

NASA Technical Reports Server (NTRS)

The optical emission attributed to electronically desorbed excited sodium atoms from NaCl and Na-evaporated surfaces is shown to be enhanced by exposure of the surface to gaseous CO2 and N2. This is the first observation of enhancement of electron-simulated desorption of substrate atoms caused by the exposure of surfaces to gaseous molecules which do not contain the desorbed atoms. The large amount of excited-sodium yield at 60 K provides evidence for nonexistence of the secondary-electron excitation of thermally desorbed ground sodium.

Xu, Jun; Albridge, Royal; Barnes, Alan; Yang, Xinxing; Tolk, Norman

1992-01-01

220

Manuel Garca Snchez-Colomer -1 Evaluacin del impacto ambiental  

E-print Network

Manuel García Sánchez-Colomer - 1 Evaluación del impacto ambiental Temas 12 - 13 Tema 13 Evaluación del impacto ambiental Temas 12 - 13 Factor del medio: medio biótico · Vegetación · Fauna terrestre ambiental Temas 12 - 13 Medio biótico: Vegetación ESTUDIO DE VEGETACIÓN DE RIBERA ­ ESTUDIO DE HÁBITATS DE

Espigares, Tíscar

221

Estrategias cognitivo-conductuales para el manejo del craving  

Microsoft Academic Search

En el presente trabajo se revisaron los aspectos genera- les del craving y se destacó su importancia para la adhe- rencia al tratamiento en adicciones. De igual manera se revisaron las diferentes estrategias cognitivo-conductua- les para el manejo del craving, las cuales incluían: detención del pensamiento, técnicas de distracción, con- trol y programación de actividades, entrenamiento en relajación, técnicas de

Iván González Salazar

2004-01-01

222

Guida alla compilazione del Piano economico on line  

E-print Network

Guida alla compilazione del Piano economico on line #12;Attenzione Questa guida fornisce indicazioni pratiche per la compilazione del Piano economico on line. Per avere indicazioni più generali sulla formulazione del Piano economico si raccomanda di fare riferimento a: Guida alla presentazione (http

De Cindio, Fiorella

223

Piano Lauree Scientifiche: Aspetti matematici del Rudiger Achilles  

E-print Network

Piano Lauree Scientifiche: Aspetti matematici del GPS R¨udiger Achilles Universit`a di Bologna Bologna, 3 Febbraio 2014 Piano Lauree Scientifiche: Aspetti matematici del GPS R¨udiger Achilles Bologna essere d. Piano Lauree Scientifiche: Aspetti matematici del GPS R¨udiger Achilles Bologna, 3 Febbraio

Achilles, Rüdiger

224

Hoja informativa sobre la calidad del aire interior  

E-print Network

promover la salud y la calidad de vida mediante la prevención y el control de las enfermedades, lasHoja informativa sobre la calidad del aire interior La mala calidad del aire interior proviene de de uso doméstico como limpiadores y pesticidas Cómo mejorar la calidad del aire interior · Abra las

225

EL TURISMO ELECTRÓNICO, UNA NECESIDAD PARA LAS EMPRESAS DEL SECTOR  

Microsoft Academic Search

La importancia y la necesidad de la utilización del Comercio Electrónico en la industria turística ayuda a mejorar las operaciones tradicionales practicadas en los negocios, tanto en la estrategia empresarial como en la reingeniería del negocio turístico. El hecho de que predominen las pequeñas y medianas empresas en el sector implica que la utilización del e-Commerce no se ha extendido

Ernesto Manuel Conde Pérez; Nel Enrique Cristian Schmidt Cornejo; Ileana Ochoa Llamas

2011-01-01

226

COMUNICATO STAMPA Nuove frontiere del Corso di Laurea in Fisioterapia  

E-print Network

in Fisioterapia intende promuovere un'ulteriore analisi della formazione universitaria del Fisioterapista rinnovamento importante della Formazione universitaria del Fisioterapista, non più ulteriormente differibile universitaria e nel profilo del Fisioterapista. E' stato richiesto l' accreditamento E.C.M. LA PARTECIPAZIONE AL

Costagliola, Gennaro

227

Departament de Filosofia del Dret i Dret Internacional Privat Presentaci  

E-print Network

Departament de Filosofia del Dret i Dret Internacional Privat Presentació El Departament de Filosofia del Dret i Dret Internacional Privat està compost per les següents àrees de coneixement: Tauler d Departament de Filosofia del Dret i Dret Internacional Privat preguen als seus alumnes que es comuniquen amb

Escolano, Francisco

228

Tratamiento biológico del lixiviado generado en el relleno sanitario \\  

Microsoft Academic Search

2 *d; además, este sistema presentó gran estabilidad frente a variaciones importantes en cuanto a las características del lixiviado y ausencia de olores desagradables. Los porcentajes de remoción de DQO en el reactor UASB eran muy variables, con picos bajos y caídas muy marcadas, que indican que no se presentaba un funcionamiento óptimo del proceso durante la mayor parte del

Alexander Álvarez Contreras; John Hermógenes; Suárez Gelvez

2006-01-01

229

Análisis del Proceso Software Basado en Modelos de Producción Industrial  

Microsoft Academic Search

La modelización del Proceso Software constituye un marco de referencia para la organización de las actividades que involucran todas las etapas del desarrollo, tendente a la resolución de problemas que el propio desarrollo de software plantea y genera a medida que evoluciona. La modelización del proceso se hace mas compleja a medida que el desarrollo tecnológico, metodológico y, fundamentalmente la

Alicia Mon

230

Recalibrando la medición del balance estructural en Chile  

Microsoft Academic Search

El presente resumen de políticas realiza una revisión sistemática de la metodología de estimación del Balance Estructural (BE) en Chile. Esta revisión no sólo recapitula y evalúa la justificación de la metodología de cálculo del BE actual o las pasadas, sino que explora diversas alternativas de mejoramiento, en la perspectiva de elevar la calidad, transparencia y estabilidad del BE como

Mario Marcel; Mabel Cabezas; Bernardita Piedrabuena

2012-01-01

231

ESPECIALIZACIN EN GESTIN AMBIENTAL Objetivo del programa  

E-print Network

ESPECIALIZACIÓN EN GESTIÓN AMBIENTAL Objetivo del programa La Especialización en Gestión Ambiental identificar, en un mundo cambiante, en lo social, en lo económico y en lo ambiental, las medidas de prevención, mitigación y resolución de problemas de carácter ambiental, a fin de contribuir con el desarrollo sostenible

Vásquez, Carlos

232

APUNTES PARA UN ESTUDIO DEL DISEÑO INDUSTRIAL  

Microsoft Academic Search

La máquina es quizá el factor dominante de nuestra época. Desde la primera mitad del XIX se desarrolla une nuevo sistema de acción sobre la materia y de producción de objetos permitiendo la multiplicación de objetos consecuencia de la producción en serie. El diseño industrial es así la forma característica de la producción de objetos de la sociedad industrial, es

Ignacio Casado Galván

2009-01-01

233

Exámenes selectivos de detección del cáncer colorrectal  

Cancer.gov

Un ejemplo excelente del poder de la investigación de prevención es el progreso sustancial que hemos logrado en la reducción de la incidencia y muerte por cáncer colorrectal, con nuevos conocimientos que iluminan el camino a incluso mayores reducciones en un futuro cercano.

234

Self Interacting Markov chains P. Del Moral  

E-print Network

-Sud Ouest, France 2 / 27 #12;Self interacting processes in biology and engineering Biology : Genetic type, bayesian learning, filtering, and spectral analysis of Feynman-Kac-Schroedinger operators. Some important-Boltzmann-Gibbs transformation : G : E [0, [ with µ(G) > 0 G (µ)(dx) = 1 µ(G) G(x) µ(dx) P. Del Moral (INRIA Bordeaux) INRIA

Del Moral , Pierre

235

Aproximaciones al análisis económico del derecho  

Microsoft Academic Search

Durante las últimas décadas la metodología de estudio que plantea el análisis económico del Derecho ha tomado gran importancia en todo el mundo,y es acompañada y respaldada por un prolífico volumen de publicaciones e investigadores, que día tras día la utilizan para evaluar los posibles caminos y consecuencias que las construcciones y desarrollos legales pueden tener sobre el comportamiento de

Mario A. Pinzón Camargo

236

VIII Encuentro Nacional de Teatro del CLETA  

E-print Network

músicos y cantantes. Unos gozan de más experiencia dentro del género y de más conocimiento técnico que otros; sin embargo, lo que está por encima de algunas posibles deficiencias técnicas es la voluntad firme de los "Cletos" de hacer teatro, de...

Frischmann, Donald H.

1983-10-01

237

EXCEPTIONAL SHEAVES ON DEL PEZZO SURFACES  

Microsoft Academic Search

In the present paper exceptional sheaves on del Pezzo surfaces are studied, and a description of rigid bundles on these surfaces is given. It is proved that each exceptional sheaf can be included in a complete exceptional collection. Furthermore, it is shown that all such collections can be obtained from each other by means of a sequence of standard operations

S. A. Kuleshov; D. O. Orlov

1995-01-01

238

PASO DEL NORTE SUMMER OZONE STUDY  

EPA Science Inventory

The Paso del Norte Summer Ozone Study was designed to evaluate potential control strategies for their efficacy in reducing ozone and carbon monoxide concentrations in the El Paso-Ciudad Juarez-Sunland Park international airshed of Texas, New Mexico, and Chihuahua. A field study ...

239

Sebastin Nieto Parra* ESTABILIDAD DEL SISTEMA  

E-print Network

Sebastián Nieto Parra* ESTABILIDAD DEL SISTEMA FINANCIERO Y REGULACI�N DE CAPITAL: EL CASO DE LOS financieros que pueden subsanar la fragilidad de los sistemas financieros y favorecer así la estabilidad de éstos. Palabras clave: sistema financiero internacional, instituciones financieras y crediticias, crisis

Paris-Sud XI, Université de

240

The origin of groundwater composition in the Pampeano Aquifer underlying the Del Azul Creek basin, Argentina.  

PubMed

The Pampean plain is the most productive region in Argentina. The Pampeano Aquifer beneath the Pampean plain is used mostly for drinking water. The study area is the sector of the Pampeano Aquifer underlying the Del Azul Creek basin, in Buenos Aires province. The main objective is to characterize the chemical and isotopic compositions of groundwater and their origin on a regional scale. The methodology used involved the identification and characterization of potential sources of solutes, the study of rain water and groundwater chemical and isotopic characteristics to deduce processes, the development of a hydrogeochemical conceptual model, and its validation by hydrogeochemical modelling with PHREEQC. Groundwater samples come mostly from a two-depth monitoring network of the "Dr. Eduardo J. Usunoff" Large Plains Hydrology Institute (IHLLA). Groundwater salinity increases from SW to NE, where groundwater is saline. In the upper basin groundwater is of the HCO3-Ca type, in the middle basin it is HCO3-Na, and in the lower basin it is ClSO4-NaCa and Cl-Na. The main processes incorporating solutes to groundwater during recharge in the upper basin are rain water evaporation, dissolution of CO2, calcite, dolomite, silica, and anorthite; cationic exchange with Na release and Ca and Mg uptake, and clay precipitation. The main processes modifying groundwater chemistry along horizontal flow at 30m depth from the upper to the lower basin are cationic exchange, dissolution of silica and anorthite, and clay precipitation. The origin of salinity in the middle and lower basin is secular evaporation in a naturally endorheic area. In the upper and middle basins there is agricultural pollution. In the lower basin the main pollution source is human liquid and solid wastes. Vertical infiltration through the boreholes annular space during the yearly flooding stages is probably the pollution mechanism of the samples at 30m depth. PMID:25747376

Zabala, M E; Manzano, M; Vives, L

2015-06-15

241

[Effects of NaCl stress on the seedling growth and K(+)- and Na(+) -allocation of four leguminous tree species].  

PubMed

Taking the pot-cultured seedlings of four leguminous tree species (Albizia julibrissin, Robinia pseudoacacia, Sophora japonica, and Gleditsia sinensis) as test materials, this paper studied their growth indices, critical salt concentration (C50), and K+ and Na+ allocation under different levels of NaCl stress, aimed to understand the difference of test tree species in salt tolerance. NaCl stress inhibited the seedling growth of the tree species. Under NaCl stress, the dry matter accumulation decreased, while the root/shoot ratio increased, especially for A. julibrissin and G. sinensis. Quadratic regression analysis showed that the C50 of A. julibrissin, R. pseudoacacia, S. japonica, and G. sinensis was 3.0 per thousand, 5.0 per thousand, 4.5 per thousand, and 3.9 per thousand, respectively, i.e., the salt tolerance of the four tree species was in the order of R. pseudoacacia > S. japonica > G. sinensis > A. julibrissin. In the root, stem, and leaf of the four tree species seedlings, the Na+ content increased with the increase of NaCl stress, while the K+ content (except in the root of A. julibrissin) decreased after an initial increase, resulting in a larger difference in the K+/Na+ ratio in the organs. Under the same NaCl stress, the allocation of Na+ in different organs of the four tree species seedlings decreased in the order of root>stem>leaf, while that of K+ differed with tree species and NaCl stress, and leaf was the main storage organ for K+. The K+/Na+ ratio in different organs decreased in the sequence of leaf>stem>root. R. pseudoacacia under NaCl stress accumulated more K+ and less Na+ in stem and leaf, and had higher K+/Na+ ratio in all organs and higher dry mass, being assessed to be more salt-tolerant. In contrast, A. julibrissin under high NaCl stress accumulated more Na+ in stem and leaf, and had a lower K+/Na+ ratio in all organs and lower dry mass, being evaluated to be lesser salt-tolerant. The K+ accumulation in seedling stem and leaf and the Na+ retention in seedling root could be the main reasons for the salt tolerance of leguminous tree species under NaCl stress. PMID:21812288

Mo, Hai-Bo; Yin, Yun-Long; Lu, Zhi-Guo; Wei, Xiu-Jun; Xu, Jian-Hua

2011-05-01

242

Characterization of NaV1.6-mediated Na+ currents in smooth muscle cells isolated from mouse vas deferens.  

PubMed

Patch-clamp experiments were performed to investigate the behavior of voltage-activated inward currents in vas deferens myocytes from Na(V)1.6-null mice (Na(V)1.6(-/-)) lacking the expression of the Na(+) channel gene, Scn8a, and their wild-type littermates (Na(V)1.6(+/+)). Immunohistochemistry confirmed expression of Na(V)1.6 in the muscle of Na(V)1.6(+/+), but not Na(V)1.6(-/-), vas deferens. PCR analysis revealed that the only beta(1)-subunit gene expressed in Na(V)1.6(+/+) vas deferens was Scn1b. In Na(V)1.6(+/+) myocytes, the threshold for membrane currents evoked by 20 msec voltage ramps (-100 mV to 60 mV) was -38.5 +/- 4.6 mV and this was shifted to a more positive potential (-31.2 +/- 4.9 mV) by tetrodotoxin (TTX). In Na(V)1.6(-/-) myocytes, the threshold was -30.4 +/- 3.4 mV and there was no TTX-sensitive current. The Na(+) current (I(Na)) in Na(V)1.6(+/+) myocytes had a bell-shaped current-voltage relationship that peaked at approximately -10 mV. Increasing the duration of the voltage ramps beyond 20 msec reduced the peak amplitude of I(Na). I(Na) displayed both fast (tau approximately 10 msec) and slow (tau approximately 1 sec) recovery from inactivation, the magnitude of the slow component increasing with the duration of the conditioning pulse (5-40 msec). During repetitive activation (5-40 msec pulses), I(Na) declined at stimulation frequencies > 0.5 Hz and at 10 Hz Na) is due solely to Na(V)1.6 in Na(V)1.6(+/+) myocytes. The gating properties of these channels suggest they play a major role in regulating smooth muscle excitability, particularly in response to rapid depolarizing stimuli. PMID:20054822

Zhu, Hai-Lei; Shibata, Atsushi; Inai, Tetsuichiro; Nomura, Masatoshi; Shibata, Yosaburo; Brock, James A; Teramoto, Noriyoshi

2010-04-01

243

El teatro argentino del año 2000 y el teatro del futuro  

E-print Network

concepto deconstructivo, con su manejo de la contaminación textual, señaló el advenimiento del intertexto posmoderno en nuestro teatro. Las nociones que Jencks (97) postula para la arquitectura posmoderna pueden emplearse para acercarse al teatro de... incluyen en esta tendencia.10 Ellos, junto a otros creadores, están protagonizando desde los primeros años de la presente década una "nueva entrada al mundo" del teatro argentino. En un ambiente limitado durante mucho tiempo a "vivir con lo nuestro...

Pellettieri, Osvaldo

2000-10-01

244

Usos del sòl i tendències de transformació a la comarca del Baix Llobregat  

Microsoft Academic Search

A partir de les dades sobre sol urbà i sol urbanitzable programat, per usos, als municipis del Baix Llobregat, s'analitzen la realitat i les potencialitats en l'ocupació del sol a la comarca. Tot seguit es passa a descriure les principals tendències de transformació en aquest camp per a un futur proper, que s'associen, fonamentalment, als grans projectes de creació d'infraestructures

Javier Sáez

2008-01-01

245

Hydrogen Sulfide Induced Disruption of Na+ Homeostasis in the Cortex  

PubMed Central

Maintenance of ionic balance is essential for neuronal functioning. Hydrogen sulfide (H2S), a known toxic environmental gaseous pollutant, has been recently recognized as a gasotransmitter involved in numerous biological processes and is believed to play an important role in the neural activities under both physiological and pathological conditions. However, it is unclear if it plays any role in maintenance of ionic homeostasis in the brain under physiological/pathophysiological conditions. Here, we report by directly measuring Na+ activity using Na+ selective electrodes in mouse cortical slices that H2S donor sodium hydrosulfide (NaHS) increased Na+ influx in a concentration-dependent manner. This effect could be partially blocked by either Na+ channel blocker or N-methyl-D-aspartate receptor (NMDAR) blocker alone or almost completely abolished by coapplication of both blockers but not by non-NMDAR blocker. These data suggest that increased H2S in pathophysiological conditions, e.g., hypoxia/ischemia, potentially causes a disruption of ionic homeostasis by massive Na+ influx through Na+ channels and NMDARs, thus injuring neural functions. Activation of delta-opioid receptors (DOR), which reduces Na+ currents/influx in normoxia, had no effect on H2S-induced Na+ influx, suggesting that H2S-induced disruption of Na+ homeostasis is resistant to DOR regulation and may play a major role in neuronal injury in pathophysiological conditions, e.g., hypoxia/ischemia. PMID:22474073

Chao, Dongman; He, Xiaozhou; Yang, Yilin; Balboni, Gianfranco; Salvadori, Severo; Kim, Dong H.; Xia, Ying

2012-01-01

246

Um novo paradigma na medicina DESENVOLVEU UMA METODOLOGIA DISRUPTIVA BASEADA NA INTEGRAO DE AVANADAS TECNOLOGIAS  

E-print Network

INTEGRAÇÃO DE AVANÇADAS TECNOLOGIAS DE GENÉTICA E MÉTODOS COMPUTACIONAIS SOFISTICADOS. OBJECTIVO? AJUDAR OS MÉDICOS A MELHORAR DIAGNÓSTICOS NA MEDICINA DO CORAÇÃO. #12;Depois do aperfeiçoamento das tecnologias pa cardíacas. A tecnologia permite analisar um elevado núme- ro de alterações genéticas em simultâneo, de for

Instituto de Sistemas e Robotica

247

Estudio para la prevención del cáncer necesita voluntarias: El Estudio del Tamoxifeno y Raloxifeno (STAR) se realiza en Norteamérica  

Cancer.gov

El Estudio del Tamoxifeno y Raloxifeno (STAR, por sus siglas en inglés), uno de los estudios más importantes realizados para la prevención del cáncer del seno, está ahora reclutando voluntarias en más de 400 centros en los Estados Unidos, Puerto Rico y Canadá.

248

Ttol: CONCURS PER A LA RENOVACI DEL LOGOTIP DEL PROGRAMA DACCI TUTORIAL (P.A.T.) DE LA FACULTAT  

E-print Network

DE FILOSOFIA I LLETRES Categoria: CONVOCAT�RIES I CONCURSOS �rgan: Facultat de Filosofia i Lletres RENOVACI� DEL LOGOTIP DEL PROGRAMA D´ACCI� TUTORIAL (P.A.T.) DE LA FACULTAT DE FILOSOFIA I LLETRES CONCURSO de Filosofia i Lletres convoca aquest concurs que té per objecte l´actualització distintiva del

Escolano, Francisco

249

Na+ transport in the normal and failing heart – remember the balance  

PubMed Central

In the heart, intracellular Na+ concentration ([Na+]i) is a key modulator of Ca2+ cycling, contractility and cardiac myocyte metabolism. Several Na+ transporters are electrogenic, thus they both contribute to shaping the cardiac action potential and at the same time are affected by it. [Na+]i is controlled by the balance between Na+ influx through various pathways, including the Na+/Ca2+ exchanger and Na+ channels, and Na+ extrusion via the Na+/K+-ATPase. [Na+]i is elevated in HF due to a combination of increased entry through Na+ channels and/or Na+/H+ exchanger and reduced activity of the Na+/K+-ATPase. Here we review the major Na+ transport pathways in cardiac myocytes and how they participate in regulating [Na+]i in normal and failing hearts. PMID:23608603

Despa, Sanda; Bers, Donald M.

2013-01-01

250

Aproximación al cálculo del crecimiento real de Colombia: aportes metodológicos para la inclusión en las cuentas nacionales de los impactos del  

Microsoft Academic Search

Resumen El sistema de contabilidad integrada considera el problema del agotamiento de los recursos naturales. En este trabajo se analiza la diferencia entre este sistema y el de cuentas nacionales utilizando datos del sector minero en Colombia para gas natural y carbón. Los resultados muestran que al incorporar los impactos del agotamiento del gas natural y del carbón el PIB

Michee Lachaud; Jorge Maldonado

2011-01-01

251

Structural Fold and Binding Sites of the Human Na+-Phosphate Cotransporter NaPi-II  

PubMed Central

Phosphate plays essential biological roles and its plasma level in humans requires tight control to avoid bone loss (insufficiency) or vascular calcification (excess). Intestinal absorption and renal reabsorption of phosphate are mediated by members of the SLC34 family of sodium-coupled transporters (NaPi-IIa,b,c) whose membrane expression is regulated by various hormones, circulating proteins, and phosphate itself. Consequently, NaPi-II proteins are also potentially important pharmaceutical targets for controlling phosphate levels. Their crucial role in Pi homeostasis is underscored by pathologies resulting from naturally occurring SLC34 mutations and SLC34 knockout animals. SLC34 isoforms have been extensively studied with respect to transport mechanism and structure-function relationships; however, the three-dimensional structure is unknown. All SLC34 transporters share a duplicated motif comprising a glutamine followed by a stretch of threonine or serine residues, suggesting the presence of structural repeats as found in other transporter families. Nevertheless, standard bioinformatic approaches fail to clearly identify a suitable template for molecular modeling. Here, we used hydrophobicity profiles and hidden Markov models to define a structural repeat common to all SLC34 isoforms. Similar approaches identify a relationship with the core regions in a crystal structure of Vibrio cholerae Na+-dicarboxylate transporter VcINDY, from which we generated a homology model of human NaPi-IIa. The aforementioned SLC34 motifs in each repeat localize to the center of the model, and were predicted to form Na+ and Pi coordination sites. Functional relevance of key amino acids was confirmed by biochemical and electrophysiological analysis of expressed, mutated transporters. Moreover, the validity of the predicted architecture is corroborated by extensive published structure-function studies. The model provides key information for elucidating the transport mechanism and predicts candidate substrate binding sites. PMID:24655502

Fenollar-Ferrer, Cristina; Patti, Monica; Knöpfel, Thomas; Werner, Andreas; Forster, Ian C.; Forrest, Lucy R.

2014-01-01

252

Regulation of persistent Na current by interactions between beta subunits of voltage-gated Na channels.  

PubMed

The beta subunits of voltage-gated Na channels (Scnxb) regulate the gating of pore-forming alpha subunits, as well as their trafficking and localization. In heterologous expression systems, beta1, beta2, and beta3 subunits influence inactivation and persistent current in different ways. To test how the beta4 protein regulates Na channel gating, we transfected beta4 into HEK (human embryonic kidney) cells stably expressing Na(V)1.1. Unlike a free peptide with a sequence from the beta4 cytoplasmic domain, the full-length beta4 protein did not block open channels. Instead, beta4 expression favored open states by shifting activation curves negative, decreasing the slope of the inactivation curve, and increasing the percentage of noninactivating current. Consequently, persistent current tripled in amplitude. Expression of beta1 or chimeric subunits including the beta1 extracellular domain, however, favored inactivation. Coexpressing Na(V)1.1 and beta4 with beta1 produced tiny persistent currents, indicating that beta1 overcomes the effects of beta4 in heterotrimeric channels. In contrast, beta1(C121W), which contains an extracellular epilepsy-associated mutation, did not counteract the destabilization of inactivation by beta4 and also required unusually large depolarizations for channel opening. In cultured hippocampal neurons transfected with beta4, persistent current was slightly but significantly increased. Moreover, in beta4-expressing neurons from Scn1b and Scn1b/Scn2b null mice, entry into inactivated states was slowed. These data suggest that beta1 and beta4 have antagonistic roles, the former favoring inactivation, and the latter favoring activation. Because increased Na channel availability may facilitate action potential firing, these results suggest a mechanism for seizure susceptibility of both mice and humans with disrupted beta1 subunits. PMID:19228957

Aman, Teresa K; Grieco-Calub, Tina M; Chen, Chunling; Rusconi, Raffaella; Slat, Emily A; Isom, Lori L; Raman, Indira M

2009-02-18

253

Na?La?(CO?)? and CsNa?Ca?(CO?)?: two new carbonates as UV nonlinear optical materials.  

PubMed

Two nonlinear optical crystal carbonates (Na4La2(CO3)5 and CsNa5Ca5(CO3)8 were successfully synthesized by hydrothermal method, and both of them crystallized in the same noncentrosymmetric hexagonal space group P63mc (No. 186). The structure of Na4La2(CO3)5 consists of a three-dimensional network made up of [CO3] triangles as well as irregular [Na(0.67)La(0.33)O10] and [NaO8] polyhedra. The structure of CsNa5Ca5(CO3)8 can be described as the standing-on-edge [CO3] groups connect the adjacent infinite [CaCO3]? layers in the ab plane to construct a framework with four types of channels running parallel to [010]. The Na, Cs, and [Na(0.67)Ca(0.33)] atoms reside in these channels. The measurement of second harmonic generation (SHG) by the method adapted from Kurtz and Perry indicated that Na4La2(CO3)5 and CsNa5Ca5(CO3)8 were phase-matchable in the visible region and exhibited SHG responses of approximately 3 and 1 × KH2PO4 (KDP). Meanwhile, they exhibited wide transparent region with short UV cutoff edge at about 235 and 210 nm, respectively, suggesting that these crystals as NLO materials may have potential applications in the UV region. PMID:25027762

Luo, Min; Wang, GenXiang; Lin, Chensheng; Ye, Ning; Zhou, Yuqiao; Cheng, Wendan

2014-08-01

254

Ionic liquid electrolytes with various sodium solutes for rechargeable Na/NaFePO4 batteries operated at elevated temperatures.  

PubMed

NaFePO4 with an olivine structure is synthesized via chemical delithiation of LiFePO4 followed by electrochemical sodiation of FePO4. Butylmethylpyrrolidinium-bis(trifluoromethanesulfonyl)imide (BMP-TFSI) ionic liquid (IL) with various sodium solutes, namely NaBF4, NaClO4, NaPF6, and NaN(CN)2, is used as an electrolyte for rechargeable Na/NaFePO4 cells. The IL electrolytes show high thermal stability (>350 °C) and nonflammability, and are thus ideal for high-safety applications. The highest conductivity and the lowest viscosity of the electrolyte are obtained with NaBF4. At an elevated temperature (above 50 °C), the IL electrolyte is more suitable than a conventional organic electrolyte for the sodium cell. At 75 °C, the measured capacity of NaFePO4 in a NaBF4-incorporated IL electrolyte is as high as 152 mAh g(-1) (at 0.05 C), which is near the theoretical value (154 mAh g(-1)). Moreover, 60% of this capacity can be retained when the charge-discharge rate is increased to 1 C. PMID:25295391

Wongittharom, Nithinai; Wang, Chueh-Han; Wang, Yi-Chen; Yang, Cheng-Hsien; Chang, Jeng-Kuei

2014-10-22

255

Na+/H+ and Na+/NH4+ exchange activities of zebrafish NHE3b expressed in Xenopus oocytes  

PubMed Central

Zebrafish Na+/H+ exchanger 3b (zNHE3b) is highly expressed in the apical membrane of ionocytes where Na+ is absorbed from ion-poor fresh water against a concentration gradient. Much in vivo data indicated that zNHE3b is involved in Na+ absorption but not leakage. However, zNHE3b-mediated Na+ absorption has not been thermodynamically explained, and zNHE3b activity has not been measured. To address this issue, we overexpressed zNHE3b in Xenopus oocytes and characterized its activity by electrophysiology. Exposure of zNHE3b oocytes to Na+-free media resulted in significant decrease in intracellular pH (pHi) and intracellular Na+ activity (aNai). aNai increased significantly when the cytoplasm was acidified by media containing CO2-HCO3? or butyrate. Activity of zNHE3b was inhibited by amiloride or 5-ethylisopropyl amiloride (EIPA). Although the activity was accompanied by a large hyperpolarization of ?50 mV, voltage-clamp experiments showed that Na+/H+ exchange activity of zNHE3b is electroneutral. Exposure of zNHE3b oocytes to medium containing NH3/NH4+ resulted in significant decreases in pHi and aNai and significant increase in intracellular NH4+ activity, indicating that zNHE3b mediates the Na+/NH4+ exchange. In low-Na+ (0.5 mM) media, zNHE3b oocytes maintained aNai of 1.3 mM, and Na+-influx was observed when pHi was decreased by media containing CO2-HCO3? or butyrate. These results provide thermodynamic evidence that zNHE3b mediates Na+ absorption from ion-poor fresh water by its Na+/H+ and Na+/NH4+ exchange activities. PMID:24401990

Ito, Yusuke; Kato, Akira; Hirata, Taku; Hirose, Shigehisa

2014-01-01

256

ZAP70 Expression Within del6q21, del11q13 and del17p13 Cytogenetic Subgroups of Iranian Patients with Chronic Lymphocytic Leukemia  

PubMed Central

Background: B-cell chronic lymphocytic leukemia (B-CLL) is the most common form of leukemia in adults. Some reports showed that expression of ZAP70 gene and chromosomal abnormality are two prognostic factors in management of B-CLL Objectives: In this study, we determined ZAP70 mRNA expression level in the del17p13, del6q21 and del11q13 subgroups of Iranian B-CLL patients to investigate prognostic value of ZAP70 expression. Patients and Methods: In this cross-sectional study, fluorescence in situ hybridization analysis was carried out on 66 Iranian B-CLL patients. Zap70 mRNA expression was evaluated by using Real Time RT-PCR. Results: Molecular analysis showed that ZAP70 expression increased 2.46 fold in the del11q13 subgroup, 2.87 fold in the del17p13 and 1.87 fold in the del6q21, compared to the 15 patients in the control group. Comparison of standard deviation and mean of the ZAP70 expression profile within the subgroups showed more variability among the cases of the del11q13 and del17p13 versus tight clustering for the del6q21. Therefore, there is a relation between del6q21 aberrations; which has good prognosis with normal levels of ZAP70 expression. Conclusions: The results of ANOVA test showed that ZAP70 expression gene was significantly increased in del17p13 and del11q13 subgroups compared to control group. Thus, ZAP70 may play an important role in the prognosis of B-CLL patients.

Jafari Ghahfarokhi, Hamideh; Ashoori, Saeede; Akbari, Mohamad Taghi; Lotfizadeh, Masoud; Karimi, Ali; Teimori, Hossein

2014-01-01

257

NA Nonlinear Equation-of-state Inversion  

NASA Astrophysics Data System (ADS)

A fully non-linear inversion scheme is introduced for the determination of the parameters controlling the equation-of-state and elasticity of mineral phases using the thermodynamically consistent finite-strain formulation introduced by Stixrude & Lithgow-Bertelloni (2005). This inversion exploits a directed search in an eight-dimensional parameter space using the Neighbourhood Algorithm (NA) of Sambridge (1999) to search for the minimum of an objective function representing the misfit to multiple data sets that constrain different aspects of the mineral behaviour. No derivatives are employed and the progress towards the minimum builds on the accumulated information on the character of the parameter space acquired as the inversion progresses. When only a limited range of experimental information is available there is a strong possibility of multiple minima in the objective function, which can pose problems for conventional iterative least-squares or other gradient methods. The addition of many different styles of data tends to produce a better defined minimum. The influence of different data types can be readily assessed by allowing differential weighting. The new procedure is illustrated by application to MgO, for which extensive experimental data are available. These include the variation of relative volume V with temperature T and pressure P from both static and shock-compression experiments, acoustic measurements of compressional and shear (and hence bulk) moduli, and calorimetric determinations of entropy as a function of temperature at atmospheric pressure. Preliminary NA modeling highlighted tensions between marginally incompatible subsets of data. We therefore excluded one-atmosphere V(T) data for T ? 1800 K for which the quasi-harmonic approximation is inadequate (Wu et al., 2008) along with elastic moduli derived from Brillouin spectroscopy under conditions (P ? 14 GPa) where significant departures from hydrostatic conditions are expected. With these limited exclusions based on sound physical principles, the NA search identified a compact family of models that provide an excellent fit to the diverse experimental data and a measure of the covariance between key model parameters.

Jackson, I.; Kennett, B. L.

2008-12-01

258

Magnesium correction to the NaKCa chemical geothermometer  

USGS Publications Warehouse

Equations and graphs have been devised to correct for the adverse effects of magnesium upon the Na-K-Ca chemical geothermometer. Either the equations or graphs can be used to determine appropriate temperature corrections for given waters with calculated NaKCa temperatures > 70??C and R 50 are probably derived from relatively cool aquifers with temperatures approximately equal to the measured spring temperature, irrespective of much higher calculated Na-K-Ca temperatures. ?? 1979.

Fournier, R.O.; Potter, R.W., II

1979-01-01

259

Interactions of Local Anesthetics with Voltage-gated Na + Channels  

Microsoft Academic Search

Voltage-gated Na+ channels are dynamic transmembrane proteins responsible for the rising phase of the action potential in excitable membranes. Local anesthetics (LAs) and structurally related antiarrhythmic and anticonvulsant compounds target specific sites in voltage-gated Na+ channels to block Na+ currents, thus reducing excitability in neuronal, cardiac, or central nervous tissue. A high-affinity LA block is produced by binding to open

C. Nau; G. K. Wang

2004-01-01

260

Simulation of Na D emission near Europa during eclipse  

USGS Publications Warehouse

The Cassini imaging science subsystem observed Europa in eclipse during Cassini's Jupiter flyby. The disk-resolved observations revealed a spatially nonuniform emission in the wavelength range of 200-1050 nm (clear filters). By building on observations and simulations of Europa's Na atmosphere and torus we find that electron-excited Na in Europa's tenuous atmosphere can account for the observed emission if the Na is ejected preferentially from Europa's dark terrain. Copyright 2008 by the American Geophysical Union.

Cassidy, T.A.; Johnson, R.E.; Geissler, P.E.; Leblanc, F.

2008-01-01

261

Sodium superionic conduction in Na2B12H12.  

PubMed

Impedance measurements indicate that Na2B12H12 exhibits dramatic Na(+) conductivity (on the order of 0.1 S cm(-1)) above its order-disorder phase-transition at ?529 K, rivaling that of current, solid-state, ceramic-based, Na-battery electrolytes. Superionicity may be aided by the large size, quasispherical shape, and high rotational mobility of the B12H12(2-) anions. PMID:24584582

Udovic, Terrence J; Matsuo, Motoaki; Unemoto, Atsushi; Verdal, Nina; Stavila, Vitalie; Skripov, Alexander V; Rush, John J; Takamura, Hitoshi; Orimo, Shin-ichi

2014-04-11

262

Metastable surface phase for Na xC 60  

NASA Astrophysics Data System (ADS)

Na xC 60 thin films with Na concentration 0 ? x ? 3 were investigated using angle-dependent photoelectron spectroscopy. For low doping we observed two distinct fulleride phases coexisting with regions of pristine C 60. One of these fulleride phase is predominantly formed close to the surface and disappears after annealing and further addition of Na. At higher doping a phase with stoichiometry of x = 3 is formed.

Schiessling, J.; Marenne, I.; Kjeldgaard, L.; Rudolf, P.

2007-09-01

263

CaMKII-dependent regulation of cardiac Na+ homeostasis  

PubMed Central

Na+ homeostasis is a key regulator of cardiac excitation and contraction. The cardiac voltage-gated Na+ channel, NaV1.5, critically controls cell excitability, and altered channel gating has been implicated in both inherited and acquired arrhythmias. Ca2+/calmodulin-dependent protein kinase II (CaMKII), a serine/threonine kinase important in cardiac physiology and disease, phosphorylates NaV1.5 at multiple sites within the first intracellular linker loop to regulate channel gating. Although CaMKII sites on the channel have been identified (S516, T594, S571), the relative role of each of these phospho-sites in channel gating properties remains unclear, whereby both loss-of-function (reduced availability) and gain-of-function (late Na+ current, INaL) effects have been reported. Our review highlights investigating the complex multi-site phospho-regulation of NaV1.5 gating is crucial to understanding the genesis of acquired arrhythmias in heart failure (HF) and CaMKII activated conditions. In addition, the increased Na+ influx accompanying INaL may also indirectly contribute to arrhythmia by promoting Ca2+ overload. While the precise mechanisms of Na+ loading during HF remain unclear, and quantitative analyses of the contribution of INaL are lacking, disrupted Na+ homeostasis is a consistent feature of HF. Computational and experimental observations suggest that both increased diastolic Na+ influx and action potential prolongation due to systolic INaL contribute to disruption of Ca2+ handling in failing hearts. Furthermore, simulations reveal a synergistic interaction between perturbed Na+ fluxes and CaMKII, and confirm recent experimental findings of an arrhythmogenic feedback loop, whereby CaMKII activation is at once a cause and a consequence of Na+ loading. PMID:24653702

Grandi, Eleonora; Herren, Anthony W.

2014-01-01

264

Synthesis of NaA zeolite membrane by microwave heating  

Microsoft Academic Search

The synthesis of NaA zeolite membrane on a porous ?-Al2O3 support by microwave heating (MH) was investigated. The formation of a NaA zeolite membrane was drastically promoted by MH. The synthesis time was reduced from 3 h for conventional heating (CH) to 15 min for MH. Surface seeding cannot only promote the formation of NaA zeolite on the support, but

Xiaochun Xu; Weishen Yang; Jie Liu; Liwu Lin

2001-01-01

265

The trafficking of Na(V)1.8.  

PubMed

The ?-subunit of tetrodotoxin-resistant voltage-gated sodium channel Na(V)1.8 is selectively expressed in sensory neurons. It has been reported that Na(V)1.8 is involved in the transmission of nociceptive information from sensory neurons to the central nervous system in nociceptive [1] and neuropathic [24] pain conditions. Thus Na(V)1.8 has been a promising target to treat chronic pain. Here we discuss the recent advances in the study of trafficking mechanism of Na(V)1.8. These pieces of information are particularly important as such trafficking machinery could be new targets for painkillers. PMID:20816723

Swanwick, Richard S; Pristerá, Alessandro; Okuse, Kenji

2010-12-10

266

The trafficking of NaV1.8  

PubMed Central

The ?-subunit of tetrodotoxin-resistant voltage-gated sodium channel NaV1.8 is selectively expressed in sensory neurons. It has been reported that NaV1.8 is involved in the transmission of nociceptive information from sensory neurons to the central nervous system in nociceptive [1] and neuropathic [24] pain conditions. Thus NaV1.8 has been a promising target to treat chronic pain. Here we discuss the recent advances in the study of trafficking mechanism of NaV1.8. These pieces of information are particularly important as such trafficking machinery could be new targets for painkillers. PMID:20816723

Swanwick, Richard S.; Pristerá, Alessandro; Okuse, Kenji

2010-01-01

267

Integrated Control of Na Transport along the Nephron.  

PubMed

The kidney filters vast quantities of Na at the glomerulus but excretes a very small fraction of this Na in the final urine. Although almost every nephron segment participates in the reabsorption of Na in the normal kidney, the proximal segments (from the glomerulus to the macula densa) and the distal segments (past the macula densa) play different roles. The proximal tubule and the thick ascending limb of the loop of Henle interact with the filtration apparatus to deliver Na to the distal nephron at a rather constant rate. This involves regulation of both filtration and reabsorption through the processes of glomerulotubular balance and tubuloglomerular feedback. The more distal segments, including the distal convoluted tubule (DCT), connecting tubule, and collecting duct, regulate Na reabsorption to match the excretion with dietary intake. The relative amounts of Na reabsorbed in the DCT, which mainly reabsorbs NaCl, and by more downstream segments that exchange Na for K are variable, allowing the simultaneous regulation of both Na and K excretion. PMID:25098598

Palmer, Lawrence G; Schnermann, Jürgen

2015-04-01

268

Pion and kaon freezeout in NA44  

SciTech Connect

The NA44 spectrometer is optimized for the study of single and two-particle particle spectra near mid-rapidity for transverse momenta below {approx} 1 GeV/c. A large fraction of all pairs in the spectrometer`s acceptance are at low relative momenta, resulting in small statistical uncertainties on the extracted size parameters. In addition, the spectrometer`s clean particle identification allows the authors to measure correlation functions for pions, kaons, and protons. This contribution will concentrate on the source size parameters determined from pion and kaon correlation functions. These size parameters will be compared to calculations from the RQMD event generator and also interpreted in the context of a hydrodynamic model. Finally, the measured single particle spectra will be examined from the viewpoint of hydrodynamics.

NA44 Collaboration

1994-12-01

269

New results from the NA57 experiment  

NASA Astrophysics Data System (ADS)

The production of hyperons in Pb-Pb and p-Be interaction at 40 A GeV/c beam momentum has been measured by the NA57 experiment. Strange particle enhancements at 40 A GeV/c are presented for the first time and compared to those measured at 158 A GeV/c. The transverse mass spectra of high statistics, high purity samples of K0S, Lgr, Xgr and OHgr particles produced in Pb-Pb collisions at 158 A GeV/c have been studied in the framework of the blast-wave model. The dependence of the freeze-out parameters on particle species and event centrality is discussed.

Bruno, G. E.; NA57 Collaboration

2004-08-01

270

Lakota na Dakota Wowapi Oti Kin  

NSDL National Science Digital Library

The Lakota na Dakota Wowapi Oti Kin is a one-stop information portal containing Internet resources on people of Lakota and Dakota descent (also known as Sioux or Siouan peoples). Created and maintained by Professor Martin Brokenleg of Augustana College and Dr. Raymond Bucko, S.J. of Creighton University, this site offers Web links in various categories including art and artists / music and musicians, bibliographic resources, demography, education, history, language resources, legal issues, maps, museums, and a host of other Lakota-related sites. For those interested in locating information in the field of Native American studies, specifically on the Sioux peoples, this site is an excellent place to begin your search.

271

Questões mais freqüentes na área de astronomia  

NASA Astrophysics Data System (ADS)

É amplamente reconhecido que as pessoas em geral têm grande fascínio e interesse pela Astronomia. Por outro lado, o conteúdo dessa área incluído no ensino formal está longe de ser abrangente e suficiente para suprir a demanda. Esse interesse permite otimizar a divulgação e o ensino não formal de Astronomia aliando a adequação do conteúdo à expectativa das pessoas. Nesse intuito, nosso trabalho busca mapear que assuntos da Astronomia despertam mais a atenção e o interesse das pessoas e o quanto disso é estimulado pela mídia, que freqüentemente aproveita-se desse interesse de forma sensacionalista, trazendo contribuições positivas e negativas. Para esta avaliação, utilizamos as pesquisas específicas e de caracterização do público que freqüentou o MAst nos anos de 2001 a 2003, pesquisa das matérias de Astronomia veiculadas na mídia escrita da cidade do Rio de Janeiro no mesmo período, além da base de dados do programa Pergunte a um astrônomo, realizado no Observatório Nacional nos anos de 1997 a 1999. Para a análise dos dados, dividimos as perguntas em dez categorias, cada uma com suas subcategorias, tomando como referência as divisões, comissões e grupos de trabalho da IAU. Apresentamos neste trabalho os resultados dessa pesquisa, que incluem, entre outros, a predominância de questões nas categorias Observação do Céu e Sistemas Planetários enquanto nos jornais dominam as notícias de Sistemas Planetários e Espaço & Astronáutica. Outro resultado interessante indicou que as dúvidas de crianças do ensino fundamental se concentram em algumas categorias enquanto as questões de adultos são mais distribuídas por todas as categorias. Os resultados dessa pesquisa serão aplicados diretamente no aperfeiçoamento das atividades do Programa de Observação de Céu, bem como na elaboração de novos projetos e eventos realizados no MAst.

Segundo, H. A. S.; Garcia, G. C.; Caretta, C. A.; Lima, F. P.

2003-08-01

272

Mercury's Na Exosphere from MESSENGER Data  

NASA Technical Reports Server (NTRS)

MESSENGER entered orbit about Mercury on March 18, 2011. Since then, the Ultraviolet and Visible Spectrometer (UWS) channel of MESSENGER's Mercury Atmospheric and Surface Composition Spectrometer (MASCS) has been observing Mercury's exosphere nearly continuously. Daily measurements of Na brightness were fitted with non-uniform exospheric models. With Monte Carlo sampling we traced the trajectories of a representative number of test particles, generally one million per run per source process, until photoionization, escape from the gravitational well, or permanent sticking at the surface removed the atom from the simulation. Atoms were assumed to partially thermally accommodate on each encounter with the surface with accommodation coefficient 0.25. Runs for different assumed source processes are run separately, scaled and co-added. Once these model results were saved onto a 3D grid, we ran lines of sight from the MESSENGER spacecraft :0 infinity using the SPICE kernels and we computed brightness integrals. Note that only particles that contribute to the measurement can be constrained with our method. Atoms and molecules produced on the nightside must escape the shadow in order to scatter light if the excitation process is resonant-light scattering, as assumed here. The aggregate distribution of Na atoms fits a 1200 K gas, with a PSD distribution, along with a hotter component. Our models constrain the hot component, assumed to be impact vaporization, to be emitted with a 2500 K Maxwellian. Most orbits show a dawnside enhancement in the hot component broadly spread over the leading hemisphere. However, on some dates there is no dawn/dusk asymmetry. The portion of the hot/cold source appears to be highly variable.

Killen, Rosemary M.; Burger, M. H.; Cassidy, T. A.; Sarantos, M.; Vervack, R. J.; McClintock, W. El; Merkel, A. W.; Sprague, A. L.; Solomon, S. C.

2012-01-01

273

Na/sup +/-H/sup +/ exchange and Na/sup +/-dependent transport systems in streptozotocin diabetic rat kidneys  

SciTech Connect

The streptozotocin-induced diabetic rat was used to test the hypothesis that Na/sup +/-H/sup +/ exchange activity in the proximal tubule luminal membrane would be increased in association with renal hypertrophy, altered glomerular hemodynamics, enhanced filtered load and tubular reabsorption of /sup 22/Na/sup +/, and stimulated /sup 22/Na= pump activity in the basolateral membrane, previously reported characteristics of this experimental animal model. Amiloride-sensitive H/sup +/ gradient-dependent Na/sup +/ uptake and Na/sup +/ gradient-dependent H/sup +/ flux were increased in brush-border membrane vesicles from the streptozotocin-treated animals. Na/sup +/ gradient-dependent uptakes of phosphate, D-glucose, L-proline, and myoinositol were decreased in the drug-induced diabetic animals. These membrane transport alterations were not found when the streptozotocin-diabetic animals were treated with insulin.

El-Seifi, S.; Freiberg, J.M.; Kinsella, F.J.; Cheng, L.; Sacktor, B.

1987-01-01

274

Mechanism of ?-Conotoxin PIIIA Binding to the Voltage-Gated Na+ Channel NaV1.4  

PubMed Central

Several subtypes of voltage-gated Na+ (NaV) channels are important targets for pain management. ?-Conotoxins isolated from venoms of cone snails are potent and specific blockers of different NaV channel isoforms. The inhibitory effect of ?-conotoxins on NaV channels has been examined extensively, but the mechanism of toxin specificity has not been understood in detail. Here the known structure of ?-conotoxin PIIIA and a model of the skeletal muscle channel NaV1.4 are used to elucidate elements that contribute to the structural basis of ?-conotoxin binding and specificity. The model of NaV1.4 is constructed based on the crystal structure of the bacterial NaV channel, NaVAb. Six different binding modes, in which the side chain of each of the basic residues carried by the toxin protrudes into the selectivity filter of NaV1.4, are examined in atomic detail using molecular dynamics simulations with explicit solvent. The dissociation constants (Kd) computed for two selected binding modes in which Lys9 or Arg14 from the toxin protrudes into the filter of the channel are within 2 fold; both values in close proximity to those determined from dose response data for the block of NaV currents. To explore the mechanism of PIIIA specificity, a double mutant of NaV1.4 mimicking NaV channels resistant to ?-conotoxins and tetrodotoxin is constructed and the binding of PIIIA to this mutant channel examined. The double mutation causes the affinity of PIIIA to reduce by two orders of magnitude. PMID:24676211

Chen, Rong; Robinson, Anna; Chung, Shin-Ho

2014-01-01

275

Effect of NaCl on nitrogen fixation of unadapted and NaCl-adapted Azolla pinnata–Anabaena azollae  

Microsoft Academic Search

Exposure of Azolla pinnata–Anabaena azollae to NaCl induced a sharp decline in nitrogenase activity. A lethal dose of NaCl (40mM) for the growth of A. pinnata–A. azollae complex could inhibit the nitrogenase activity by 39%, revealing for higher sensitivity of general growth to NaCl than the nitrogenase activity. Salinity caused a distinct shift in the profile of heterocyst differentiation in

Vandna Rai; S. P. Tiwari; Ashwani K. Rai

2001-01-01

276

Adherencia del tratamiento antibiótico en los cuadros  

Microsoft Academic Search

OBJETIVO: Evaluar la adherencia del tratamiento antibiótico observada en pacientes con cuadros infecciosos no complicados y tratados con diversas pautas antibióticas.\\u000aDISEÑO: Estudio observacional y prospectivo desde 2003 hasta 2008. ÁMBITO DE ESTUDIO: Dos centros de atención primaria de Cataluña.\\u000aSUJETOS: Pacientes de 18 años o más con sospecha de infección de etiología bacteriana de faringe, tracto respiratorio inferior, tracto

Nuria Sierra Montalbán; Silvia Hernández Anadón; Carles Llor Vilà; Ana Moragas Moreno; Marta Hernández Anadón; Carolina Bayona Faro

2010-01-01

277

Premio Ollantay 1989 - Acta del jurado  

E-print Network

, personas e instituciones cuyas trayectorias, dedicadas al desarrollo del teatro a nivel continental, ameriten ser destacadas como ejemplo. El Jurado designado por el CELCIT para otorgar los Premios Ollantay correspondientes al año 1989, integrado por... Colombia 2. Grupo de Teatro al Teatro Imagen, de Chile 3. Institución de Apoyo al Teatro al Consejo Nacional de Ciencia y Tecnología, CONCYTEC, de Perú 4. Teatro Infantil al Grupo de Teatro de Muñecos "Quijotillo," de Cumaná, Venezuela 5. Publicación...

1990-04-01

278

III Festival del Siglo de Oro (Chamizal)  

E-print Network

y los Estados Unidos, administrado por el Servicio Nacional de Parques como homenaje a la buena voluntad interamericana. Cuenta con una amplia sala de teatro donde se realizan muchas funciones culturales bilingües. Allá se celebró del 7 al 18 de... Tirso de Molina. Los grupos 112 LATIN AMERICAN THEATRE REVIEW participantes fueron invitados desde México, Venezuela, y la región sureña de los Estados Unidos. Se dividieron en dos categorías, grupos académicos y de reper torio, y compitieron por...

Jaraba-Pardo, E.

1978-04-01

279

Estimating the hydrogen ion concentration in concentrated NaCl and Na{sub 2}SO{sub 4} electrolytes  

SciTech Connect

Combination glass electrodes were tested for determining H{sup +} concentrations in concentrated pure and mixed NaCl and Na{sub 2}SO{sub 4} solutions, as well as natural brine systems. NaCl, Na{sub 2}SO{sub 4}, and mixtures of NaCl and Na{sub 2}SO{sub 4} solutions were analyzed. Correction factors for estimating pC{sub H}{sup +} (negative logarithm of H{sup +} concentration) were determined from measured/observed pH values. Required Gran-type titrations were done with HCl and/or NaOH. The titration method is described and a step-by-step procedure provided; it has been used previously for determining pC{sub H}{sup +} values of synthetic chloride-dominated brines. Precautions are required to determine correction factors for electrolytes that react with H{sup +} or OH{sup {minus}} [sulfate brines for titration with acid; magnesium brines for titration with base because of precipitation of Mg(OH)2]. Correction factors A (pC{sub H}{sup +} = pH{sub ob} + A) from HCl titrations were similar to those from NaOH titrations where the concentration of free H{sup +} was calculated using a thermodynamic model. These values should be applicable to solns with a very large range in measured pH values (2 to 12). Because a large number of solns were titrated with HCl and the A values are similar for HCl and NaOH titrations, the A values for NaCl and Na2SO4 solns were fit as a function of molality to allow extrapolation. For NaCl solns 0 to 6.0 M, A can be obtained by multiplying the molality by 0.159. For Na2SO4 solns 0 to 2.0 M, the values of A can be obtained from (0.221 {minus} 0.549X + 0.201X{sup 2}), where X is the molality of Na{sub 2}SO{sub 4}. Orion-Ross electrode evaluations indicated that the A values did not differ significantly for different electrodes. Results suggest that the data in this report can be used to estimate A values for different NaCl and Na{sub 2}SO{sub 4} solns even for noncalibrated electrodes.

Rai, D.; Felmy, A.R.; Juracich, S.P.; Rao, F. [Pacific Northwest Lab., Richland, WA (United States)

1995-06-01

280

Relation of membrane vesicles to volume control and Na+-transport in smooth muscle: studies on Na+-rich tissues.  

PubMed

Correlation between operation of a volume control system (independent of Na+-K+ -ATPase) and membrane vesicle structure was examined in strips of rat myometrium made Na-rich by incubation in Krebs-Ringer solutions at 5 degrees C. Some pieces of tissue were analyzed for Na+, K+, ATP and water contents before and after rewarming to 37 degrees C. Other pieces of tissue were prepared and examined in the electron microscope. The membrane vesicles along the surface of the muscle cells were reduced from the numberin fresh tissues made Na+-rich by overnight incubation in K+-free Ringer solution at 5 degrees C. Rewarming of Na+-rich tissues under conditions thought to inhibit Na+-K+-ATPase caused the loss of Na+ with water and with utake of K+ but the vesicles did not increase in number. Na+-K+ATPase activity was suggested to inhibit vesicle formation by competing for ATP. The loss of water and increase in vesicle number was Ca2+-dependent but did not require Na+. Inhibition of the volume control system by iodoacetamide, Ca2+-free solution and other procedures resulted in swelling of membrane vesicles. The membrane vesicles were suggested to be sites of a mechanochemical system of volume control and the mechanochemical step was suggested to involve discharge of membrane vesicles. PMID:157384

Garfield, R E; Daniel, E E

1977-06-01

281

Kinetics and stoichiometry of coupled Na efflux and Ca influx (Na\\/Ca exchange) in barnacle muscle cells  

Microsoft Academic Search

ABSTRACT,Coupled,Na § exit\\/Ca 2+ entry (Na\\/Ca exchange,operating,in the Ca 2+ influx mode),was studied,in giant barnacle,muscle,cells by measuring,~Na + efflux and 4~Ca2+ influx in internally perfused, ATP-fueled cells in which the Na + pump was poisoned by 0.1 mM ouabain. Internal free Ca ~+, [Ca ~+ ]i, was controlled with a Ca-EGTA buffering,system,containing,8 mM,EGTA and,varying,amounts,of Ca ~+. Ca ~+ sequestration,in internal

HECTOR RASGADO-FLORES; ELIGIO M. SANTIAGO; MORDECAI P. BLAUSTEIN

1989-01-01

282

Kinetics and stoichiometry of coupled Na efflux and Ca influx (Na/Ca exchange) in barnacle muscle cells  

PubMed Central

Coupled Na+ exit/Ca2+ entry (Na/Ca exchange operating in the Ca2+ influx mode) was studied in giant barnacle muscle cells by measuring 22Na+ efflux and 45Ca2+ influx in internally perfused, ATP-fueled cells in which the Na+ pump was poisoned by 0.1 mM ouabain. Internal free Ca2+, [Ca2+]i, was controlled with a Ca-EGTA buffering system containing 8 mM EGTA and varying amounts of Ca2+. Ca2+ sequestration in internal stores was inhibited with caffeine and a mitochondrial uncoupler (FCCP). To maximize conditions for Ca2+ influx mode Na/Ca exchange, and to eliminate tracer Na/Na exchange, all of the external Na+ in the standard Na+ sea water (NaSW) was replaced by Tris or Li+ (Tris-SW or LiSW, respectively). In both Na-free solutions an external Ca2+ (Cao)-dependent Na+ efflux was observed when [Ca2+]i was increased above 10(-8) M; this efflux was half-maximally activated by [Ca2+]i = 0.3 microM (LiSW) to 0.7 microM (Tris-SW). The Cao-dependent Na+ efflux was half-maximally activated by [Ca2+]o = 2.0 mM in LiSW and 7.2 mM in Tris-SW; at saturating [Ca2+]o, [Ca2+]i, and [Na+]i the maximal (calculated) Cao-dependent Na+ efflux was approximately 75 pmol#cm2.s. This efflux was inhibited by external Na+ and La3+ with IC50's of approximately 125 and 0.4 mM, respectively. A Nai-dependent Ca2+ influx was also observed in Tris-SW. This Ca2+ influx also required [Ca2+]i greater than 10(-8) M. Internal Ca2+ activated a Nai-independent Ca2+ influx from LiSW (tracer Ca/Ca exchange), but in Tris-SW virtually all of the Cai-activated Ca2+ influx was Nai-dependent (Na/Ca exchange). Half-maximal activation was observed with [Na+]i = 30 mM. The fact that internal Ca2+ activates both a Cao-dependent Na+ efflux and a Nai- dependent Ca2+ influx in Tris-SW implies that these two fluxes are coupled; the activating (intracellular) Ca2+ does not appear to be transported by the exchanger. The maximal (calculated) Nai-dependent Ca2+ influx was -25 pmol/cm2.s. At various [Na+]i between 6 and 106 mM, the ratio of the Cao-dependent Na+ efflux to the Nai-dependent Ca2+ influx was 2.8-3.2:1 (mean = 3.1:1); this directly demonstrates that the stoichiometry (coupling ratio) of the Na/Ca exchange is 3:1. These observations on the coupling ratio and kinetics of the Na/Ca exchanger imply that in resting cells the exchanger turns over at a low rate because of the low [Ca2+]i; much of the Ca2+ extrusion at rest (approximately 1 pmol/cm2.s) is thus mediated by an ATP-driven Ca2+ pump.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:2769225

1989-01-01

283

Kinetics and stoichiometry of coupled Na efflux and Ca influx (Na/Ca exchange) in barnacle muscle cells.  

PubMed

Coupled Na+ exit/Ca2+ entry (Na/Ca exchange operating in the Ca2+ influx mode) was studied in giant barnacle muscle cells by measuring 22Na+ efflux and 45Ca2+ influx in internally perfused, ATP-fueled cells in which the Na+ pump was poisoned by 0.1 mM ouabain. Internal free Ca2+, [Ca2+]i, was controlled with a Ca-EGTA buffering system containing 8 mM EGTA and varying amounts of Ca2+. Ca2+ sequestration in internal stores was inhibited with caffeine and a mitochondrial uncoupler (FCCP). To maximize conditions for Ca2+ influx mode Na/Ca exchange, and to eliminate tracer Na/Na exchange, all of the external Na+ in the standard Na+ sea water (NaSW) was replaced by Tris or Li+ (Tris-SW or LiSW, respectively). In both Na-free solutions an external Ca2+ (Cao)-dependent Na+ efflux was observed when [Ca2+]i was increased above 10(-8) M; this efflux was half-maximally activated by [Ca2+]i = 0.3 microM (LiSW) to 0.7 microM (Tris-SW). The Cao-dependent Na+ efflux was half-maximally activated by [Ca2+]o = 2.0 mM in LiSW and 7.2 mM in Tris-SW; at saturating [Ca2+]o, [Ca2+]i, and [Na+]i the maximal (calculated) Cao-dependent Na+ efflux was approximately 75 pmol#cm2.s. This efflux was inhibited by external Na+ and La3+ with IC50's of approximately 125 and 0.4 mM, respectively. A Nai-dependent Ca2+ influx was also observed in Tris-SW. This Ca2+ influx also required [Ca2+]i greater than 10(-8) M. Internal Ca2+ activated a Nai-independent Ca2+ influx from LiSW (tracer Ca/Ca exchange), but in Tris-SW virtually all of the Cai-activated Ca2+ influx was Nai-dependent (Na/Ca exchange). Half-maximal activation was observed with [Na+]i = 30 mM. The fact that internal Ca2+ activates both a Cao-dependent Na+ efflux and a Nai-dependent Ca2+ influx in Tris-SW implies that these two fluxes are coupled; the activating (intracellular) Ca2+ does not appear to be transported by the exchanger. The maximal (calculated) Nai-dependent Ca2+ influx was -25 pmol/cm2.s. At various [Na+]i between 6 and 106 mM, the ratio of the Cao-dependent Na+ efflux to the Nai-dependent Ca2+ influx was 2.8-3.2:1 (mean = 3.1:1); this directly demonstrates that the stoichiometry (coupling ratio) of the Na/Ca exchange is 3:1. These observations on the coupling ratio and kinetics of the Na/Ca exchanger imply that in resting cells the exchanger turns over at a low rate because of the low [Ca2+]i; much of the Ca2+ extrusion at rest (approximately 1 pmol/cm2.s) is thus mediated by an ATP-driven Ca2+ pump.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:2769225

Rasgado-Flores, H; Santiago, E M; Blaustein, M P

1989-06-01

284

Complete Bromide Surface Segregation in Mixed NaCl /NaBr Aerosols Grown from Droplets  

NASA Astrophysics Data System (ADS)

Sea-salt aerosols are a source of atmospheric bromine responsible for ozone depletion. The availability of bromine from sea-salt aerosols to heterogeneous phase chemical reactions is determined by its local concentration at the aerosol surface. We report here complete surface segregation of bromine in mixed NaCl /NaBr aerosols grown by drying droplets, thus mimicking the atmospheric process by which solid sea-salt aerosols are generated. For d =70 nm solid aerosols, complete surface segregation is observed for solution Br /Cl ratios below 2%. These findings set a size-dependent upper limit on the bromine surface enrichment that can be reached in solid salt aerosols grown from sea-water droplets in the atmosphere.

Antonsson, Egill; Patanen, Minna; Nicolas, Christophe; Neville, John J.; Benkoula, Safia; Goel, Alok; Miron, Catalin

2015-01-01

285

Kinetic and thermodynamic uranyl (II) adsorption process into modified Na-Magadiite and Na-Kanemite.  

PubMed

The compound 2-mercaptopyrimidine (MPY) was attached onto synthetic Na-Magadiite (M) and Na-Kanemite (K) samples by homogeneous route. The final matrices named M(MPY) and K(MPY) have been characterized through X-ray powder diffraction and scanning electron microscopy (SEM). The resulted materials were submitted to process of adsorption with uranyl solution at pH 2.0 and 298+/-1K. The kinetic parameters were analyzed by the Lagergren and Elovich models of adsorption and demonstrated to be good fit for all experiments. From calorimetric determinations the quantitative thermal effects for uranyl(II)/basic center interactions gave exothermic enthalpy, negative Gibbs free energy, and positive entropy. These thermodynamic data confirmed the energetically favorable condition of such interactions at the solid/liquid interface for all systems. PMID:19155125

Guerra, Denis Lima; Pinto, Alane Azevedo; de Souza, Janaína Azevedo; Airoldi, Claudio; Viana, Rúbia Ribeiro

2009-07-30

286

H + , Na + , K + , and Amino Acid Transport in Caterpillar and Larval Mosquito Alimentary Canal  

Microsoft Academic Search

\\u000a Two principal strategies are used to energize membranes in living organisms, a Na+ strategy and a voltage strategy. In the Na+ strategy a primary Na+\\/K+ ATPase imposes both Na+ and K+ concentration gradients across cell membranes with Na+ high outside and K+ high inside the cells. The Na+ gradient, ?[Na+] is used to drive diverse secondary transporters. For example, in

William R. Harvey; Bernard A. Okech

287

EDITORIAL: TaCoNa-Photonics 2008 TaCoNa-Photonics 2008  

Microsoft Academic Search

This special section on theoretical and computational nano-photonics features papers presented at the first International Workshop on Theoretical and Computational Nano-Photonics (TaCoNa-Photonics 2008) held in Bad Honnef, Germany, 3-5 December 2008. The workshop covered a broad range of topics related to current developments and achievements in this interdisciplinary area of research. Since the late 1960s, the word `photonics' has been

Dmitry N. Chigrin; Kurt Busch; Andrei V. Lavrinenko

2009-01-01

288

Peroxisome proliferator-activated receptor gamma antagonists decrease Na+ transport via the epithelial Na+ channel.  

PubMed

The epithelial sodium channel (ENaC) is believed to represent the rate-limiting step for sodium absorption in the renal collecting duct. Consequently, ENaC is a central effector affecting systemic blood volume and pressure. Sodium and water transport are dysregulated in diabetes mellitus. Peroxisome proliferator-activated receptor gamma (PPARgamma) agonists are currently used in the treatment of type 2 diabetes, although their use remains limited by fluid retention. The effects of PPARgamma agonists on ENaC activity remain controversial. Although PPARgamma agonists were shown to stimulate ENaC-mediated renal salt absorption, probably via the serum- and glucocorticoid-regulated kinase 1, other studies reported that the PPARgamma agonist-induced fluid retention is independent of ENaC activity. Here we confirmed that four chemically distinct PPARgamma agonists [pioglitazone, rosiglitazone, troglitazone, and 15-deoxy-Delta12,14-prostaglandin J2 (PGJ2)] do not enhance Na+ transport in cultured renal collecting duct principal mpkCCDc14 cells, as assessed by short-circuit current measurements. However, the PPARgamma antagonist 2-chloro-5-nitro-N-4-pyridinyl-benzamide (T0070907), and to a lesser extent 2-chloro-5-nitrobenzanilide (GW9662), were found to decrease Na+ reabsorption across mpkCCDc14 cell layers. Furthermore, pretreatment of monolayers with T0070907 diminished the insulin-stimulated sodium transport. PPARgamma agonist PGJ2 did not enhance insulin-stimulated Na+ flux via ENaC. We also show that PPARgamma enhances ENaC activity when all three subunits are reconstituted in Chinese hamster ovary (CHO) cells. GW9662 inhibits ENaC activity when ENaC subunits are coexpressed in CHO cells with PPARgamma. In contrast, rosiglitazone has no effect on ENaC activity. We conclude that PPARgamma activity is important for maintaining basal and insulin-dependent transepithelial Na+ transport and ENaC activity. PMID:19752200

Pavlov, Tengis S; Levchenko, Vladislav; Karpushev, Alexey V; Vandewalle, Alain; Staruschenko, Alexander

2009-12-01

289

El uso de la neuromodulación para el tratamiento del temblor  

PubMed Central

Introducción: El temblor puede ser un desorden incapacitante y el tratamiento de primera línea para estos pacientes es farmacológico. Sin embargo, este tratamiento puede llevar a una reducción satisfactoria del temblor en sólo el 50% de los pacientes con temblor esencial. La talamotomía era el tratamiento de elección para el temblor refractario al tratamiento médico hasta que comenzó a utilizarse la estimulación cerebral profunda (ECP) del núcleo ventral intermedio (Vim) del tálamo. En la actualidad, raramente se realiza la talamotomía. Métodos: Este artículo es una revisión no sistemática de las indicaciones, resultados, parámetros de programación y técnica quirúrgica de la ECP del Vim para el tratamiento del temblor. Resultados: Aunque los resultados clínicos son similares usando la talamotomía o la ECP del Vim, la primera causa más efectos adversos que la última. Además, la ECP puede ser usada bilateralmente, mientras que la talamotomía tiene un alto riesgo de causar disartria cuando se realiza de ambos lados. La ECP del Vim logró una adecuada mejoría del temblor en varias series de pacientes con temblor causado por temblor esencial, enfermedad de Parkinson o esclerosis múltiple. Además del Vim, hay otros blancos que están siendo usados por varios autores, tales como la zona incerta y las radiaciones prelemniscales. Conclusión: La ECP del Vim es un tratamiento útil para el temblor incapacitante refractario al tratamiento médico. Es esencial realizar una precisa selección de pacientes, así como utilizar una técnica quirúrgica correcta. Aún se desconoce el mejor blanco estereotáctico para el temblor, aunque el Vim es el más usado. PMID:25165613

Bendersky, Damián; Ajler, Pablo; Yampolsky, Claudio

2014-01-01

290

Stimulation of Na+/K+ ATPase activity and Na+ coupled glucose transport by ?-catenin.  

PubMed

?-Catenin is a multifunctional protein stimulating as oncogenic transcription factor several genes important for cell proliferation. ?-Catenin-regulated genes include the serum- and glucocorticoid-inducible kinase SGK1, which is known to stimulate a variety of transport systems. The present study explored the possibility that ?-catenin influences membrane transport. To this end, ?-catenin was expressed in Xenopus oocytes with or without SGLT1 and electrogenic transport determined by dual electrode voltage clamp. As a result, expression of ?-catenin significantly enhanced the ouabain-sensitive current of the endogeneous Na(+)/K(+)-ATPase. Inhibition of vesicle trafficking by brefeldin A revealed that the stimulatory effect of ?-catenin on the endogenous Na(+)/K(+)-ATPase was not due to enhanced stability of the pump protein in the cell membrane. Expression of ?-catenin further enhanced glucose-induced current (Ig) in SGLT1-expressing oocytes. In the absence of SGLT1 Ig was negligible irrespective of ?-catenin expression. The stimulating effect of ?-catenin on both Na(+)/K(+) ATPase and SGLT1 activity was observed even in the presence of actinomycin D, an inhibitor of transcription. The experiments disclose a completely novel function of ?-catenin, i.e. the regulation of transport. PMID:20951116

Sopjani, Mentor; Alesutan, Ioana; Wilmes, Jan; Dërmaku-Sopjani, Miribane; Lam, Rebecca S; Koutsouki, Evgenia; Jakupi, Muharrem; Föller, Michael; Lang, Florian

2010-11-19

291

The imprint of subduction fluids on subducted MORB-derived melts (Sierra del Convento Mélange, Cuba)  

NASA Astrophysics Data System (ADS)

Major and trace element signatures and Sr-Nd-Pb isotope data for muscovite (Ms)-bearing amphibolite blocks and associated muscovite-bearing trondhjemite and quartz-muscovite rocks from the Sierra del Convento mélange (eastern Cuba) indicate that Proto-Caribbean oceanic crust underwent wet partial melting processes during Mesozoic subduction and after accretion to the upper plate. Trace element normalized patterns of Ms-bearing amphibolites are enriched in light rare earth elements (LREE) and large-ion lithophile elements (LILE) and evidence variable trace element transfer from the Proto-Caribbean subducting slab to the mantle wedge. Ms-bearing trondhjemites show LREE enrichment and HREE depletion and have geochemical features similar to adakites, including SiO 2 > 56 wt.%, high Na 2O contents (5.5-9.0 wt.%) and high Sr/Y (16-644). We consider that the trondhjemites represent primary and natural melts formed by deep partial melting of the subducting slab which did not significantly react with the mantle wedge before intrusion in the subduction channel. The Ms-bearing trondhjemites show different geochemical and petrological signatures compared with the Ms-free tonalites-trondhjemites from Sierra del Convento, that are interpreted as primary slab melts. These differences support the idea that partial melting processes in the Sierra del Convento subduction channel were triggered by the infiltration of fluids derived from three distinct subducted sources: sediments, altered mid-ocean ridge basalts (MORB), and serpentinites. In this scenario, the pegmatitic quartz-muscovite rocks, which are highly enriched in LILE, probably represent the crystallization products of fluids derived by differentiation of the trondhjemitic melts.

Lázaro, C.; Blanco-Quintero, I. F.; Marchesi, C.; Bosch, D.; Rojas-Agramonte, Y.; García-Casco, A.

2011-10-01

292

Synthesis and Structure of 1D Na6 Cluster Chain with Short Na-Na Distance: Organic like Aromaticity in Inorganic Metal Cluster  

E-print Network

A unique 1D chain of sodium cluster containing (Na6) rings stabilized by a molybdenum containing metalloligand has been synthesized and characterized. DFT calculations show striking resemblance in their aromatic behaviour with the corresponding hydrocarbon analogues

Khatua, S; Chattaraj, P K; Roy, D R; Bhattacharjee*, Manish; Chattaraj*, Pratim K.; Khatua, Snehadrinarayan; Roy, Debesh R.

2006-01-01

293

Morphology, geology and geochemistry of the "Salar del Gran Bajo del Gualicho" (Rio Negro, Argentina)  

USGS Publications Warehouse

A multidisciplinary study of the Gran Bajo del Gualicho area (Rio Negro - Argentina) was carried out; the aim was to delineate its geological and geomorphological evolution and to estabilish the genesis of salts filling the depression. Climatic conditions were analized first to individuate their role in the present morphogenetic processes; moreover the main morphological features of present landscape were examined as well as the stratigraphy of the outcropping formations, and of the Gran Bajo del Gualicho Formation in particular. Finally, a possible geomorphological evolution of the studied area was traced. Geophysical analyses allowed to estabilish that the paleosurface shaped on the crystalline basement is strongly uneven and shows evidence of the strong tectonic phases it underwent. The result of isotope analyses confirmed that the salt deposits on the Gran Bajo del Gualicho bottom were produced by fresh water evaporation, while strontium isotope ratio suggested that such waters were responsible for solubilization of more ancient evaporitic deposits.

Angelucci, A.; Barbieri, M.; Brodtkorb, A.; Ciccacci, S.; Civitelli, G.; De Barrio, R.; Di, Filippo M.; Fredi, P.; Friedman, I.; Lombardi, S.; Schalamuk, A.I.; Toro, B.

1996-01-01

294

On the dynamic influence of Na+ in Mercury's magnetotail  

NASA Astrophysics Data System (ADS)

Although initially ionized at low (<10 eV) energies in Mercury's dayside magnetosphere, Na+ ions can become energized via non-adiabatic motion in the plasma sheet to energies as high as several keV. Although present in sufficient abundance to contribute to both plasma pressure and mass density, the collective influence of Na+ has not yet been confirmed. Here, observations by the Fast Imaging Plasma Spectrometer and Magnetometer on the MErcury Surface Space Environment, GEochemistry, and Ranging spacecraft demonstrate that Na+ can contribute substantially to the total pressure in Mercury's plasma sheet. We identify several examples of sustained high fluxes of Na+ particle flux that are shown to contribute to the diamagnetic depressions measured in the plasma sheet. The three-dimensional distribution functions of Na+ for these events are consistent with hot, nearly isotropic Maxwell-Boltzmann distributions. The relative pressure contribution of Na+ to the total plasma sheet content at Mercury is highly asymmetric, increasing from ~1-30% from dawn to dusk. We further identify an increase in magnetic fluctuations near the Na+ gyro-frequency at the dusk-side magnetopause when the Na+ content of the plasma sheet exceeds 1/cc. These fluctuations are non-linear and highly compressive and do not appear to be the simple left-hand-polarized ion cyclotron wave mode. Instead, these waves transition from left-hand near the magnetopause to right-hand polarization deeper inside the magnetosphere, penetrating up to high latitudes.

Gershman, Daniel J.; Raines, Jim M.; Slavin, James A.; Zurbuchen, Thomas H.; Sundberg, Torbjorn; Boardsen, Scott A.; Anderson, Brian J.; Korth, Haje; Solomon, Sean C.

2014-05-01

295

Performances of the NA48 Liquid Krypton calorimeter  

E-print Network

The NA48 experiments aims at a precise measurement of direct CP violation in the neutral Kaon system. This puts stringent requirements on the electromagnetic calorimeter used to detect photons of average energy 25 GeV. The choice of NA48 is a quasi homogeneous Liquid Krypton calorimeter with fast readout. The operation of this device and the performances achieved are described.

Guillaume Unal

2000-12-05

296

Annelid epithelia as models for electrogenic Na+ transport.  

PubMed

The electrogenic Na(+) absorption across tight epithelia from invertebrates follows the principles analog to the mechanisms found in vertebrates. Extracellular Na(+)-ions pass the apical cell membranes through highly selective Na(+) channels and follow an electrochemical gradient which is sustained by the basolateral Na(+)/K(+)-ATPases. These apical Na(+) channels are selectively blocked by amiloride and represent the rate-limiting target for the control of transcellular Na(+) uptake. Although annelids express ADH-like peptide hormones, they lack the osmoregulatory mineralocorticoid system with the vertebrate-specific key hormone aldosterone. Thus, their epithelia may represent interesting models for investigation of ion transport regulation. While the formation of urine in the nephridia of, for example, leeches had been subject to intensive studies, the investigation of ion transport across their body wall was largely neglected. We use dissected segments of integuments from the limnic leech Hirudo medicinalis and, recently, from the earthworm Lumbricus terrestris for Ussing chamber experiments. We investigate transintegumental ion transport with focus on control of electrogenic Na(+) uptake and the amiloride-sensitive part of it and identified several extracellular factors as peptide hormones, tri- and divalent cations or purinergic molecules with regulatory effects on it. Meanwhile, there exists a macroscopic view on Na(+) absorption; however, other ion transport mechanisms across annelid integuments still await scientific effort. Here we present a concise synopsis about the electrophysiology of annelid integuments to illustrate the state of science and to evaluate whether further studies in this particular field may be of interest. PMID:12421540

Schnizler, Mikael; Krumm, Steffen; Clauss, Wolfgang

2002-11-13

297

Hydration of Na+ in the interlayer of hectorite: a  

E-print Network

1 Hydration of Na+ , Ni2+ , and Sm3+ in the interlayer of hectorite: a quasielastic neutron.com Abstract Quasielastic neutron scattering experiments were performed with Na-hectorite, Ni-hectorite, and Sm-hectorite and bound to the clay surface (inner-sphere complex). The results obtained for the Sm-hectorite were

Paris-Sud XI, Université de

298

Fragmentation of Na3 clusters following He impact: Theoretical analysis  

E-print Network

Fragmentation of Na3 ¿ clusters following He impact: Theoretical analysis of fragmentation of Na3 cluster ion fragmentation following excitation by a fast He atom is studied using a theoretical cluster. Four simple fragmentation mechanisms are proposed to describe the major features of the process

Reid, Scott A.

299

BIOLOGICAL SAFETY O N/A Biosafety Cabinets  

E-print Network

: _________________________________________________ _________________________________________________ _________________________________________________ NOTES: LASER SAFETY O N/A __LS-1 Area not posted with appropriate 3b/4 laser sign __LS-2 No lighted Other Laser Safety FindingBIOLOGICAL SAFETY O N/A Biosafety Cabinets ___BS-1 Grates obstructed ___BS-2 Not certified

Entekhabi, Dara

300

Modelo da Gestão da Cadeia de Abastecimento na Construção  

Microsoft Academic Search

Resumo Na indústria em geral, e principalmente na construção, a entrega dos recursos necessários à actividade é um factor essencial para o sucesso do negócio. Para tal contribui, em grande medida, a logística interna da própria empresa. A definição de um modelo de gestão da cadeia de abastecimento para a indústria da construção é, impreterivelmente, uma das formas de optimizar

Tiago Pinho; José Telhada; Maria Sameiro Carvalho

301

Sepsis does not alter red blood cell glucose metabolism or Na+ concentration: A 2H-, 23Na-NMR study  

SciTech Connect

The effects of sepsis on intracellular Na+ concentration ((Na+)i) and glucose metabolism were examined in rat red blood cells (RBCs) by using 23Na- and 2H-nuclear magnetic resonance (NMR) spectroscopy. Sepsis was induced in 15 halothane-anesthetized female Sprague-Dawley rats by using the cecal ligation and perforation technique; 14 control rats underwent cecal manipulation without ligation. The animals were fasted for 36 h, but allowed free access to water. At 36 h postsurgery, RBCs were examined by 23Na-NMR by using dysprosium tripolyphosphate as a chemical shift reagent. Human RBCs from 17 critically ill nonseptic patients and from 7 patients who were diagnosed as septic were also examined for (Na+)i. Five rat RBC specimens had (Na+)i determined by both 23Na-NMR and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). For glucose metabolism studies, RBCs from septic and control rats were suspended in modified Krebs-Henseleit buffer containing (6,6-2H2)glucose and examined by 2H-NMR. No significant differences in (Na+)i or glucose utilization were found in RBCs from control or septic rats. There were no differences in (Na+)i in the two groups of patients. The (Na+)i determined by NMR spectroscopy agreed closely with measurements using ICP-AES and establish that 100% of the (Na+)i of the RBC is visible by NMR. Glucose measurements determined by 2H-NMR correlated closely (correlation coefficient = 0.93) with enzymatic analysis. These studies showed no evidence that sepsis disturbed RBC membrane function or metabolism.

Hotchkiss, R.S.; Song, S.K.; Ling, C.S.; Ackerman, J.J.; Karl, I.E. (Washington Univ. School of Medicine, St. Louis (USA))

1990-01-01

302

LiNa5Mo9O30  

PubMed Central

The tite compound, lithium penta­sodium nona­molybdate, LiNa5Mo9O30, was synthesized by solid-state reaction. The three-dimensional [Mo9O30]6? framework is built up from MoO6 octa­hedra and MoO5 bipyramids, linked together by edges and corners. The framework delimits two types of inter­secting tunnels running along [100] and [010] in which the Na+ and Li+ ions are located. The asymmetric unit contains one Mo, one Na and one Li site located on a twofold rotation axis. The crystal studied was a racemic twin with site a twin ratio of 0.51?(10):0.49?(10). Relationships between the structures of K2Mo3O10, K2Mo4O13, Cs2Mo7O22, Na6Mo10O33 and Na6Mo11O36 compounds are discussed. PMID:23284311

Hamza, Hamadi; Ennajeh, Ines; Zid, Mohamed Faouzi; Driss, Ahmed

2012-01-01

303

The Na-K-ATPase and Calcium-Signaling Microdomains  

NSDL National Science Digital Library

The Na-K-ATPase is an energy-transducing ion pump that converts the free energy of ATP into transmembrane ion gradients. It also serves as a functional receptor for cardiotonic steroids such as ouabain and digoxin. Binding of ouabain to the Na-K-ATPase can activate calcium signaling in a cell-specific manner. The exquisite calcium modulation via the Na-K-ATPase is achieved by the ability of the pump to integrate signals from numerous protein and non-protein molecules, including ion transporters, channels, protein kinases/phosphatases, as well as cellular Na+. This review focuses on the unique properties of the Na-K-ATPase and its role in the formation of different calcium-signaling microdomains.

Jiang Tian (University of Toledo Health Science Campus Physiology and Pharmacology)

2008-08-01

304

Binding energy and geometry of e^+Na  

NASA Astrophysics Data System (ADS)

We calculate the non-adiabatic binding energy and geometry of the weakly bound state of e^+Na. We use the Peach model potential to describe the e^+-Na^+ and e^--Na^+ interactions and solve the effective three-body Schrödinger equation with the finite element method. Because the model potential gives rise to three spurious states (corresponding to 1s, 2s, and 2p), the true non-adiabatic ground state of e^+Na is embedded in a dense spectrum of spurious states. We developed a technique for extracting the correct ground state for e^+Na, even when the energy is nearly degenerate with a spurious level. This is the first calculation to include the quadrupole term in the polarization potential.

Shertzer, Janine; Ward, S. J.

2010-03-01

305

Feasibility study for a secondary Na/S battery  

NASA Technical Reports Server (NTRS)

The feasibility of a moderate temperature Na battery was studied. This battery is to operate at a temperature in the range of 100-150 C. Two kinds of cathode were investigated: (1) a soluble S cathode consisting of a solution of Na2Sn in an organic solvent and (2) an insoluble S cathode consisting of a transition metal dichalcogenide in contact with a Na(+)ion conducting electrolyte. Four amide solvents, dimethyl acetamide, diethyl acetamide, N-methyl acetamide and acetamide, were investigated as possible solvents for the soluble S cathode. Results of stability and electrochemical studies using these solvents are presented. The dialkyl substituted amides were found to be superior. Although the alcohol 1,3-cyclohexanediol was found to be stable in the presence of Na2Sn at 130 C, its Na2Sn solutions did not appear to have suitable electrochemical properties.

Abraham, K. M.; Schiff, R.; Brummer, S. B.

1979-01-01

306

Role of Na+,K+-pumps and transmembrane Na+,K+-distribution in muscle function. The FEPS lecture - Bratislava 2007.  

PubMed

Na(+),K(+)-ATPase situated in the plasma membrane mediates active extrusion of Na(+) and intracellular accumulation of K(+). This transport system the Na(+),K(+)-pump is the major regulator of the transmembrane distribution of Na(+) and K(+), and is itself subject to regulation by a wide variety of factors in skeletal muscles. The excitation of skeletal muscles is elicited by a rapid influx of Na(+), followed by an equivalent efflux of K(+) across sarcolemmal and t-tubular membranes. Due to their size and sudden onset, these events constitute the major transport challenge for the Na(+),K(+)-pumps. Skeletal muscles contain the largest single pool of K(+) in the organism. During intense exercise, the Na(+),K(+)-pumps cannot readily reaccumulate K(+) into the muscle cells. Therefore, the working muscles undergo a net loss of K(+), causing up to a doubling of the K(+) concentration in the arterial blood plasma in less than 1 min and even larger increases in interstitial K(+). This may induce depolarization, loss of excitability and force, in particular in muscles, where the excitation-induced passive Na(+),K(+)-fluxes are large. During continuous stimulation of isolated rat muscles, there is a highly significant correlation between the rise in extracellular K(+) and the rate of force decline. Fortunately, excitation increases the Na(+),K(+)-pumping rate within seconds. Thus, maximum activation of up to 20-fold above the resting transport rate may be reached in 10 s, with utilization of all available Na(+),K(+)-pumps. In muscles, where excitability is reduced by pre-exposure to high [K(+)]o, acute activation of the Na(+),K(+)-pumps by hormones or intermittent electrical stimulation restores excitability and contractility. In working muscles, the Na(+),K(+)-pumps, due to rapid activation of their large transport capacity, play a dynamic regulatory role in the from second to second ongoing restoration and maintenance of excitability and force. Excitation is a self-limiting process that depends on the leak/pump ratio for Na(+) and K(+). Acute inhibition of the Na(+),K(+)-pumps with ouabain or downregulation of the Na(+),K(+)-pump capacity clearly reduces contractile endurance in isolated muscles. The Na(+),K(+)-pumps are a limiting factor for contractile force and endurance. This is in particular noted if their capacity is reduced because of inactivity or disease. For these reasons, tight regulation of the Na(+),K(+)-pumps is crucial for the maintenance of plasma K(+), membrane potential and excitability in skeletal muscle. This is achieved by: (1) acute activation of the Na(+),K(+)-pumps elicited by excitation, catecholamines, insulin, insulin-like growth factor I, calcitonins and amylin; and (2) long-term regulation of the content of Na(+),K(+)-pumps exerted by thyroid hormones, adrenal steroids, insulin, training, inactivity, fasting, K(+)-deficiency or K(+)-overload. In conclusion, the Na(+),K(+)-pump is a central target for regulation of Na(+),K(+)-distribution, important for the contractile performance of skeletal muscles, the pathophysiology of several diseases and for therapeutic intervention. PMID:17988242

Clausen, T

2008-03-01

307

Genome Sequences of Cupriavidus metallidurans Strains NA1, NA4, and NE12, Isolated from Space Equipment  

PubMed Central

Cupriavidus metallidurans NA1, NA4, and NE12 were isolated from space and spacecraft-associated environments. Here, we report their draft genome sequences with the aim of gaining insight into their potential to adapt to these environments. PMID:25059868

Monsieurs, Pieter; Mijnendonckx, Kristel; Provoost, Ann; Venkateswaran, Kasthuri; Ott, C. Mark; Leys, Natalie

2014-01-01

308

Effects of oligomycin on transient currents carried by Na+ translocation of Bufo Na+/K(+)-ATPase expressed in Xenopus oocytes.  

PubMed

Na(+)/K(+)-ATPase (NKA) exports 3Na(+) and imports 2K(+) at the expense of the hydrolysis of 1ATP under physiological conditions. In the absence of K(+), it can mediate electroneutral Na(+)/Na(+) exchange. In the electroneutral Na(+)/Na(+) exchange mode, NKA produces a transient current containing fast, medium and slow components in response to a sudden voltage step. These three components of the transient current demonstrate the sequential release of Na(+) ions from three binding sites. Our data from oocytes provide further experimental support for the existence of these components. Oligomycin is an NKA inhibitor that favors the 2Na(+)-occluded state without affecting the conformational state of the NKA. We studied the effects of oligomycin on both K(+)-activated currents and transient currents in wild-type Bufo NKA and a mutant form of Bufo NKA, NKA: G813A. Oligomycin blocked almost all of the K(+)-activated current, although the three components of the transient current showed different sensitivities to oligomycin. The oligomycin-inhibited charge movement measured using a P/4 protocol had a rate coefficient similar to the medium transient component. The fast component of the transient current elicited by a short voltage step also showed sensitivity to oligomycin. However, the slow component was not totally inhibited by oligomycin. Our results indicate that the second and third sodium ions might be released to the extracellular medium by a mechanism that is not shared by the first sodium ion. PMID:21877177

Ding, Yanli; Hao, Jingping; Rakowski, Robert F

2011-10-01

309

Compressibilities of disordered fluoride pyrochlores NaCdZn 2F 7 and NaCaMg 2F 7  

NASA Astrophysics Data System (ADS)

The compressibilities of disordered pyrochlores NaCaMg 2F 7 and NaCdZn 2F 7 (both Fd3¯m, Z=8) have been studied with X-ray single-crystal and powder diffraction using diamond anvil cells to 6.5 and 9.0 GPa at room temperature, respectively. The compressibility data are fitted with the Murnaghan equations of state. The zero-pressure bulk modulus B0 and the unit-cell volume at ambient pressure V0 (for the fixed first pressure derivative of the bulk modulus B'=4.00) are equal to 83(2) GPa and 1107.12(1.33) Å 3 for NaCdZn 2F 7 and to 83(5) GPa and 1079.29(2.62) Å 3 for NaCaMg 2F 7. Upon decreasing the unit-cell volume, the positional x parameter of the F(2) atom increases in NaCdZn 2F 7 but is constant in NaCaMg 2F 7. In both cases, the (Na,Cd)F 8 and (Na,Ca)F 8 cubes become more regular and are softer than the ZnF 6 and MgF 6 octahedra, respectively. Both materials are structurally stable at least to the respective highest pressures reached in this study. These observations are compared to the high-pressure behavior of oxide pyrochlores.

Grzechnik, Andrzej; Posse, Jose Maria; Morgenroth, Wolfgang; Friese, Karen

2007-07-01

310

Genome Sequences of Cupriavidus metallidurans Strains NA1, NA4, and NE12, Isolated from Space Equipment.  

PubMed

Cupriavidus metallidurans NA1, NA4, and NE12 were isolated from space and spacecraft-associated environments. Here, we report their draft genome sequences with the aim of gaining insight into their potential to adapt to these environments. PMID:25059868

Monsieurs, Pieter; Mijnendonckx, Kristel; Provoost, Ann; Venkateswaran, Kasthuri; Ott, C Mark; Leys, Natalie; Van Houdt, Rob

2014-01-01

311

SISTEMA PARA GESTIONAR LA ACTIVIDAD CIENTÍFICA DEL DEPARTAMENTO DE INFORMÁTICA DE LA UNIVERSIDAD DE GUANTÁNAMO  

Microsoft Academic Search

El sistema para gestionar la actividad científica del Departamento de Informática de la Universidad de Guantánamo surge debido a la necesidad de gestionar de manera más rápida, segura y eficaz los procesos que se desarrollan actualmente en dicho centro. Fue desarrollado utilizando los lenguajes PHP del lado del servidor con CodeIgniter como framework y JavaScript del lado del cliente. Se

Denis Boizan Romero

2012-01-01

312

Consejera de Administraciones Pblicas y Portavoz del Gobierno Direccin General de Modernizacin  

E-print Network

. En esta segunda vía se inscribe la iniciativa del Repositorio Institucional del Principado de su autoarchivo los resultados de la investigación en el Repositorio Institucional del Principado de, favoreciendo el aumento del impacto del trabajo desarrollado por los investigadores y las instituciones

313

Reevaluation of the $^{22}$Na(p,$?$) reaction rate: Implications for the detection of $^{22}$Na gamma rays from novae  

E-print Network

Understanding the processes which create and destroy $^{22}$Na is important for diagnosing classical nova outbursts. Conventional $^{22}$Na(p,$\\gamma$) studies are complicated by the need to employ radioactive targets. In contrast, we have formed the particle-unbound states of interest through the heavy-ion fusion reaction, $^{12}$C($^{12}$C,n)$^{23}$Mg and used the Gammasphere array to investigate their radiative decay branches. Detailed spectroscopy was possible and the $^{22}$Na(p,$\\gamma$) reaction rate has been re-evaluated. New hydrodynamical calculations incorporating the upper and lower limits on the new rate suggest a reduction in the yield of $^{22}$Na with respect to previous estimates, implying a reduction in the maximum detectability distance for $^{22}$Na $\\gamma$ rays from novae.

D. G. Jenkins; C. J. Lister; R. V. F. Janssens; T. L. Khoo; E. F. Moore; K. E. Rehm; B. Truett; A. H. Wuosmaa; M. Freer; B. R. Fulton; J. Jose

2003-12-16

314

On the 21Na(p,gamma)22Mg thermonuclear rate for 22Na production in novae  

E-print Network

Classical novae are potential sources of gamma-rays, like the 1.275 MeV gamma emission following 22Na beta decay, that could be detected by appropriate instruments on board of future satellites like INTEGRAL. It has been shown that the production of 22Na by novae is affected by the uncertainty on the 21Na(p,gamma)22Mg rate and in particular by the unknown partial widths of the Ex = 5.714 MeV, J^pi = 2^+, 22Mg level. To reduce these uncertainties, we performed shell model calculations with the OXBASH code, compared the results with available spectroscopic data and calculated the missing partial widths. Finally, we discuss the influence of these results on the 21Na(p,gamma)22Mg reaction rate and 22Na synthesis.

Nadya A. Smirnova; Alain Coc

2000-08-16

315

Direct measurements of 22Na(p,g)23Mg resonances and consequences for 22Na production in classical novae  

E-print Network

The radionuclide 22Na is a potential astronomical observable that is expected to be produced in classical novae in quantities that depend on the thermonuclear rate of the 22Na(p,g)23Mg reaction. We have measured the strengths of low-energy 22Na(p,g)23Mg resonances directly and absolutely using a radioactive 22Na target. We find the strengths of resonances at E_p = 213, 288, 454, and 610 keV to be higher than previous measurements by factors of 2.4 to 3.2, and we exclude important contributions to the rate from proposed resonances at E_p = 198, 209, and 232 keV. The 22Na abundances expected in the ejecta of classical novae are reduced by a factor of ~ 2.

A. L. Sallaska; C. Wrede; A. Garcia; D. W. Storm; T. A. D. Brown; C. Ruiz; K. A. Snover; D. F. Ottewell; L. Buchmann; C. Vockenhuber; D. A. Hutcheon; J. A. Caggiano

2010-09-24

316

Raman spectroscopic study of synthesized Na-bearing majoritic garnets  

NASA Astrophysics Data System (ADS)

Majoritic garnets in diamond have been considered as the sample from mantle transition zone (e.g. Moore and Gurney, 1985). For non-destructive, in-situ Raman analysis, Gillet et al. (2002) systematically checked chemistry and Raman peak of various majoritic garnets in diamond. They treated majoritic component as number of excess-silica than 3.0 per formula unit. However, in the basaltic system, majorite garnets also have significant amounts of Na. Na substitution is coupled with Si and Ti as follows; Na +Ti = Ca +Al (Ringwood and Lovering, 1970), Na +Si = Ca + Al (Sobolev and Labrentav, 1971; Ringwood and Major, 1971) or Na + Si = Mg + Al (Gasparik, 1989). Each component in garnet is defined as follows; Mj (majorite) component = ((Si-3)-Na)/2), NaSi (Na2MSi5O12 where M= Ca, Mg, Fe2+) component = (Na-T)/2, and NaTi component = Ti/2. Okamoto and Maruyama (2003) conducted UHP experiments in the MORB + H2O system (KNCFMATSH) at 10-19 GPa. They show that 1) Mj and NaTi component are constant and lower than 0.1 at T = 900 \\deg C, and 2) NaSi component increases drastically above 15 GPa although it is neglibly small at P<15 GPa. Raman spectra was newly analyzed using Okamoto and Maruyama (2003)'s run charges. Above 15 GPa, there is a characteristic sharp peak at 910 cm-1 and broad shoulder between 800 and 900 cm-1 as well as broad band near 960 cm-1. Gillet et at (2002) concluded that the former peak at 910cm-1 is the only reliable signature for the majoritic garnet (Si>3). They also implied that the latter two broad peaks are diagnostic feature for Ti rich garnet (> 1wt% of TiO2) as well as peak at 1030 cm-1. However, in all P range (10-19 GPa) of the present study, TiO2 is higher than 1wt%, and there is a peak at 1030 cm-1. Additional Ti-free experiment at 16 GPa, 1200 \\deg C clearly revealed that Na-bearing majoritic garnet has a significant shoulder at 800-900 cm-1. Ref; Gasparik (1989) CMP, 102,389, Gillet et al. (2002) Am.Min., 87, 312, Moore and Gurney (1985)Nature, 318, 553, Okamoto and Maruyama (2003)PEPI, in press, Ringwood and Lovering (1970) EPSL, 7, 371, Ringwood and Major (1971)EPSL, 12, 411, Sobolev and Labrentav (1971)CMP, 31, 1.

Okamoto, K.

2003-12-01

317

Efecto del Programa de Entrenamiento “Manejo del Dolor” en la Documentación de Enfermería en el Expediente Electrónico  

PubMed Central

Resumen En el presente trabajo se muestra la importancia de entrenar al personal de enfermería para mejorar la documentación en el expediente electrónico. Se eligió el manejo del dolor por ser un área prioritaria; una alta proporción de pacientes en período post operatorio cursa con dolor, por lo tanto, la documentación debe ser útil para la toma de decisiones clínicas. Se implementó un programa de entrenamiento denominado “Manejo del Dolor” dirigido al personal de enfermería. Se utilizó la tecnología de la información como herramienta para fortalecer el conocimiento con base en la revisión sistemática de la literatura; el personal de enfermería participante seleccionó la mejor evidencia; posteriormente se trabajó en la transferencia de este conocimiento a la práctica a través del diseño de un protocolo para el manejo del dolor. Se concluye que el conocimiento del manejo del dolor es fundamental para que enfermería documente con mayor precisión sus intervenciones. PMID:24199106

Monsiváis, María Guadalupe Moreno; Guzmán, Ma. Guadalupe Interial; Flores, Paz Francisco Sauceda; Arreola, Leticia Vázquez

2012-01-01

318

Effects of dietary Na+ deprivation on epithelial Na+ channel (ENaC), BDNF, and TrkB mRNA expression in the rat tongue  

Microsoft Academic Search

BACKGROUND: In rodents, dietary Na+ deprivation reduces gustatory responses of primary taste fibers and central taste neurons to lingual Na+ stimulation. However, in the rat taste bud cells Na+ deprivation increases the number of amiloride sensitive epithelial Na+ channels (ENaC), which are considered as the \\

Tao Huang; Frauke Stähler

2009-01-01

319

Ethylene Oxidation over Platinum: In SituElectrochemically Controlled Promotion Using Na–??? Alumina and Studies with a Pt(111)\\/Na Model Catalyst  

Microsoft Academic Search

Electrochemically modified ethylene oxidation over a Pt film supported on the Na+ion conductor ??? alumina has been studied over a range of conditions encompassing both promotion and poisoning. The system exhibits reversible behavior, and the data are interpreted in terms of (i) Na-enhanced oxygen chemisorption and (ii) poisoning of the surface by accumulation of Na compounds. At low Na coverages

Ian R. Harkness; Christopher Hardacre; Richard M. Lambert; Ioannis V. Yentekakis; Constantinos G. Vayenas

1996-01-01

320

The C Terminus of Na+,K+-ATPase Controls Na+ Affinity on Both Sides of the Membrane through Arg935*?  

PubMed Central

The Na+,K+-ATPase C terminus has a unique location between transmembrane segments, appearing to participate in a network of interactions. We have examined the functional consequences of amino acid substitutions in this region and deletions of the C terminus of varying lengths. Assays revealing separately the mutational effects on internally and externally facing Na+ sites, as well as E1-E2 conformational changes, have been applied. The results pinpoint the two terminal tyrosines, Tyr1017 and Tyr1018, as well as putative interaction partners, Arg935 in the loop between transmembrane segments M8 and M9 and Lys768 in transmembrane segment M5, as crucial to Na+ activation of phosphorylation of E1, a partial reaction reflecting Na+ interaction on the cytoplasmic side of the membrane. Tyr1017, Tyr1018, and Arg935 are furthermore indispensable to Na+ interaction on the extracellular side of the membrane, as revealed by inability of high Na+ concentrations to drive the transition from E1P to E2P backwards toward E1P and inhibit Na+-ATPase activity in mutants. Lys768 is not important for Na+ binding from the external side of the membrane but is involved in stabilization of the E2 form. These data demonstrate that the C terminus controls Na+ affinity on both sides of the membrane and suggest that Arg935 constitutes an important link between the C terminus and the third Na+ site, involving an arginine-? stacking interaction between Arg935 and the C-terminal tyrosines. Lys768 may interact preferentially with the C terminus in E1 and E1P forms and with the loop between transmembrane segments M6 and M7 in E2 and E2P forms. PMID:19416970

Toustrup-Jensen, Mads S.; Holm, Rikke; Einholm, Anja Pernille; Schack, Vivien Rodacker; Morth, J. Preben; Nissen, Poul; Andersen, Jens Peter; Vilsen, Bente

2009-01-01

321

A mutation in Na(+)-NQR uncouples electron flow from Na(+) translocation in the presence of K(+).  

PubMed

The sodium-pumping NADH:ubiquinone oxidoreductase (Na(+)-NQR) is a bacterial respiratory enzyme that obtains energy from the redox reaction between NADH and ubiquinone and uses this energy to create an electrochemical Na(+) gradient across the cell membrane. A number of acidic residues in transmembrane helices have been shown to be important for Na(+) translocation. One of these, Asp-397 in the NqrB subunit, is a key residue for Na(+) uptake and binding. In this study, we show that when this residue is replaced with asparagine, the enzyme acquires a new sensitivity to K(+); in the mutant, K(+) both activates the redox reaction and uncouples it from the ion translocation reaction. In the wild-type enzyme, Na(+) (or Li(+)) accelerates turnover while K(+) alone does not activate. In the NqrB-D397N mutant, K(+) accelerates the same internal electron transfer step (2Fe-2S ? FMNC) that is accelerated by Na(+). This is the same step that is inhibited in mutants in which Na(+) uptake is blocked. NqrB-D397N is able to translocate Na(+) and Li(+), but when K(+) is introduced, no ion translocation is observed, regardless of whether Na(+) or Li(+) is present. Thus, this mutant, when it turns over in the presence of K(+), is the first, and currently the only, example of an uncoupled Na(+)-NQR. The fact the redox reaction and ion pumping become decoupled from each other only in the presence of K(+) provides a switch that promises to be a useful experimental tool. PMID:25486106

Shea, Michael E; Mezic, Katherine G; Juárez, Oscar; Barquera, Blanca

2015-01-20

322

An evening at "La Clinica del Pueblo".  

PubMed

This article describes a typical evening at the Clinica del Pueblo in the Hispanic neighborhood of Adams-Morgan in Washington, D.c. The Clinical del Pueblo began operating in 1983 in response to the urgen medical needs of Central American refugees arriving in the Washington D.c. area. The refugees bring with them severe trauma, fear, and health problems caused by the civil was and exacerbated by inadequate or non-existant health services. Approximately 80,000 Salvadoran refugees live in the area. They do not receive adequate health care for 3 reasons. 1) Because the US goverment is unwilling to recognize them as true refugees, they live with the constant threat of deportatin back to the violence from which they have fled. 2) Refugees lack the ability to pay for private care. 3) Langauage and culture create frightening barriers to health care for the refugees. For those who do seek care, these barriers can lead to the inadequate or incomplete diagnoses and poor compliance and follow-up. Plenty International and the Central American Refugee Center responded to these problems by organizing a free clinic to provide not only medical care but also a training course for volunteers. The director of the clinic organizes the course, the classes are taught by a variety of people including the clinic's volunteer physicians, nurses, and public health educators as well as graduates of previus training courses and people from the wider community. The services of the clinic reach only a small portion of the population in need. However, the fact that free medical services are now available to some Central American refugees make the Clinica del Pueblo an important program. PMID:12281149

Shefsky, M L

1986-01-01

323

RELACIÓN MÉDICO PACIENTE: DERECHOS DEL ADULTO MAYOR  

PubMed Central

Existen prejuicios en relación con la vejez, incluso entre los profesionales que se dedican a la gerontología. Uno común y peligroso es considerar que los viejos son todos enfermos o discapacitados. La relación médico-paciente es la piedra angular de la práctica y ética médicas. Para alcanzar el respeto por los adultos mayores es necesaria una medicina prudente, basada en una práctica en la cual la reflexión ética y clínica pueda contribuir. Esto último es posible si se hacen valer los derechos del adulto mayor, en particular como paciente para la toma de decisiones. PMID:20379380

Barrantes-Monge, Melba; Rodríguez, Eduardo; Lama, Alexis

2009-01-01

324

Manual del espectrógrafo multifunción de Bosque Alegre  

NASA Astrophysics Data System (ADS)

Este manual consta de 120 páginas y resume las características del Espectrógrafo Multifunción instalado en el telescopio de 1.54 m de la Estación Astrofísica de Bosque Alegre. En este trabajo se describen, además, las técnicas a emplear para su puesta a punto y la secuencia de operaciones para la obtención de datos en cada uno de los modos que ya se encuentran en funcionamiento. Parte de este trabajo se realizó con el apoyo de la Asociación Argentina de Astronomía, a través de becas otorgadas a R.D. y S.P..

Díaz, R.; Paolantonio, S.; Carranza, G.; Goldes, G.

325

EXPERIENCIAS EN LA ENSEÑANZA DEL COMERCIO ELECTRÓNICO EN LA UNIVERSIDAD DE PINAR DEL RÍO  

Microsoft Academic Search

El desarrollo del Comercio Electrónico es uno de los objetivos de la política de informatización de la sociedad cubana, y en este sentido se labora en la creación de infraestructuras y la capacitación de los recursos humanos necesarios. Las universidades cubanas ya incluyen en sus planes de estudio este tema, cuyo aprendizaje contribuye a formar profesionales de mayor calidad para

Lisbet Martínez Gil

2010-01-01

326

Scheda del programma definitivo ITPS 2013-2014-Prof.ssa Antonietta Lanza Obiettivo del corso  

E-print Network

specifiche in SILAD preparatorie alla prova di laboratorio. E' pianificata una prova in itinere a metà corso prova di laboratorio e una prova scritta. La prova di laboratorio (prova parziale in ESSE3) mira analisi molto limitata) mediante un programma in linguaggio Java. L'esito della prova di laboratorio è del

Malerba, Donato

327

Huave de San Mateo del Mar, Oaxaca (Huave of San Mateo del Mar, Oaxaca).  

ERIC Educational Resources Information Center

This document is one of 17 volumes on indigenous Mexican languages and is the result of a project undertaken by the Archivo de Lenguas Indigenas de Mexico. This volume contains information on Huave, an indigenous language of Mexico spoken in San Mateo del Mar, in the state of Oaxaca. The objective of collecting such a representative sampling of…

Mexico Coll. (Mexico City)

328

El crimen como oficio: una interpretación del aprendizaje del delito en Colombia  

Microsoft Academic Search

El objetivo de este trabajo es proponer un marco de análisis que permita entender el aprendizaje del delito en Colombia. El articulo supone que el delito puede ser entendido como un actividad que requiere cierta experticia. En esta medida, el crimen requiere una compleja y extensa preparación, lo cual va en contra de la creencia de que cualquier persona, en

Isaac De León Beltrán; Eduardo S. Albarán

2003-01-01

329

CARACTERÍSTICAS DEL DIRECTIVO RESPONSABLE DEL ÁREA INTERNACIONAL Y RESULTADO EXPORTADOR DE LAS EMPRESAS INDUSTRIALES  

Microsoft Academic Search

RESUMEN La creencia de que la intensidad exportadora de las empresas puede estar ocasionada por barreras internas ha generado un cuerpo de investigación sobre la influencia de las características de los directivos responsables del área internacional (DRAI) en el inicio de las operaciones de exportación, la adopción de un papel activo en la intensificación de las exportaciones o el logro

Del Río Araújo

2005-01-01

330

Análisis del dispositivo de balón coil para la oclusión del Ductus Arterioso Persistente  

Microsoft Academic Search

RESUMEN: El ductus arterioso persistente (PDA) es uno de los defectos cardiacos congénitos más comunes. Consiste en una comunicación vascular anormal durante la vida extrauterina, entre la aorta descendente y la arteria pulmonar izquierda. El PDA puede llevar al desarrollo de complicaciones importantes como hipertensión pulmonar, edema pulmonar y endocarditis bacteriana. Actualmente el manejo del PDA se hace por medio

A. C. Silva; J. C. Briceño; A. García

331

Evaluacin de Diseo 2009 del Programa I. DATOS DE IDENTIFICACIN DEL PROGRAMA  

E-print Network

Presupuesto B00 Instituto Politécnico Nacional, Yoloxóchitl Bustamante Díez , Directora General D00 Instituto este análisis puedan retroalimentar el diseño y la gestión del programa VII. Costo total de la evaluación externa, especificando la fuente de financiamiento. Costo total: $500,000 Fuente de financiamiento

332

EL PERRO DEL HORTELANO: DEFINIENDO EL ROL EMPRESARIAL DEL ESTADO EN LATINOAMÉRICA  

Microsoft Academic Search

Las fuentes de agua fresca son abundantes en el Perú, sin embargo los peruanos tienen el segundo nivel de acceso más bajo a agua potable y desagüe en Sudamérica. Sólo el 72 por ciento de los hogares tienen acceso a agua potable por cañería (pero no se atreven a tomarla del grifo) y sólo el 51 por ciento tiene acceso

Carlos Patrón

2006-01-01

333

EL PLURIVERSO DEL AGUA. DISCURSOS, IMAGINARIOS Y CONTRATOS EN EL CONFLICTO DEL AGUA  

Microsoft Academic Search

Un buen modo de abordar el conflicto del agua consiste en prestar atención al nivel de los discursos. De este modo se puede poner de manifiesto los modos tan distintos de experimentar e interpretar la realidad que tienen los actores que en tal conflicto inter- vienen. Ahora bien, como algunos discursos enunciados no tienen el suficiente poder retórico y político

J. Ángel B ERGUA

334

EFICIENCIA DEL USO DEL AGUA EN LA PRODUCCIÓN AGRICOLA EN GUATEMALA  

Microsoft Academic Search

Los estudios de ciclo de vida, hasta hoy en día, han tenido en cuenta principalmente, los flujos de energía y materiales, no existiendo acuerdo en como tratar el recurso agua, siendo éste uno de los factores que deberían considerarse, especialmente en los sistemas de producción agrícolas. El manejo del agua en agricultura, asociado a su escasez, es uno de los

Willian E. de León; Asunción Antón

335

Respuestas a las preguntas del ejercicio de ``La Expansi'on del Universo y la Ley de Hubble''  

E-print Network

Respuestas a las preguntas del ejercicio de ``La Expansi'on del Universo y la Ley de Hubble'' --La constante de Hubble, H, debe de salir alrededor de 70 km s \\Gamma1 Mpc \\Gamma1 . El tiempo transcurrido desde el inicio del Universo ser'a t = D=V . Pero por otra parte, la constante de Hubble es H = V=D, de

Rodriguez, Luis F.

336

Blockade of Na+ channels in pancreatic ?-cells has antidiabetic effects.  

PubMed

Pancreatic ?-cells express voltage-gated Na(+) channels (NaChs), which support the generation of electrical activity leading to an increase in intracellular calcium, and cause exocytosis of glucagon. Ranolazine, a NaCh blocker, is approved for treatment of angina. In addition to its antianginal effects, ranolazine has been shown to reduce HbA1c levels in patients with type 2 diabetes mellitus and coronary artery disease; however, the mechanism behind its antidiabetic effect has been unclear. We tested the hypothesis that ranolazine exerts its antidiabetic effects by inhibiting glucagon release via blockade of NaChs in the pancreatic ?-cells. Our data show that ranolazine, via blockade of NaChs in pancreatic ?-cells, inhibits their electrical activity and reduces glucagon release. We found that glucagon release in human pancreatic islets is mediated by the Nav1.3 isoform. In animal models of diabetes, ranolazine and a more selective NaCh blocker (GS-458967) lowered postprandial and basal glucagon levels, which were associated with a reduction in hyperglycemia, confirming that glucose-lowering effects of ranolazine are due to the blockade of NaChs. This mechanism of action is unique in that no other approved antidiabetic drugs act via this mechanism, and raises the prospect that selective Nav1.3 blockers may constitute a novel approach for the treatment of diabetes. PMID:24812428

Dhalla, Arvinder K; Yang, Ming; Ning, Yun; Kahlig, Kristopher M; Krause, Michael; Rajamani, Sridharan; Belardinelli, Luiz

2014-10-01

337

Electron scattering in graphene with adsorbed NaCl nanoparticles  

NASA Astrophysics Data System (ADS)

In this work, the results of contactless magnetoconductance and Raman spectroscopy measurements performed for a graphene sample after its immersion in NaCl solution were presented. The properties of the immersed sample were compared with those of a non-immersed reference sample. Atomic force microscopy and electron spin resonance experiments confirmed the deposition of NaCl nanoparticles on the graphene surface. A weak localization signal observed using contactless magnetoconductance showed the reduction of the coherence length after NaCl treatment of graphene. Temperature dependence of the coherence length indicated a change from ballistic to diffusive regime in electron transport after NaCl treatment. The main inelastic scattering process was of the electron-electron type but the major reason for the reduction of the coherence length at low temperatures was additional, temperature independent, inelastic scattering. We associate it with spin flip scattering, caused by NaCl nanoparticles present on the graphene surface. Raman spectroscopy showed an increase in the D and D' bands intensities for graphene after its immersion in NaCl solution. An analysis of the D, D', and G bands intensities proved that this additional scattering is related to the decoration of vacancies and grain boundaries with NaCl nanoparticles, as well as generation of new on-site defects as a result of the decoration of the graphene surface with NaCl nanoparticles. The observed energy shifts of 2D and G bands indicated that NaCl deposition on the graphene surface did not change carrier concentration, but reduced compressive biaxial strain in the graphene layer.

Drabi?ska, Aneta; Ka?mierczak, Piotr; Bo?ek, Rafa?; Karpierz, Ewelina; Wo?o?, Agnieszka; Wysmo?ek, Andrzej; Kami?ska, Maria; Pasternak, Iwona; Krajewska, Aleksandra; Strupi?ski, W?odek

2015-01-01

338

The rat Na + –sulfate cotransporter rNaS2: functional characterization, tissue distribution, and gene ( slc13a4 ) structure  

Microsoft Academic Search

Inorganic sulfate is essential for numerous functions in mammalian physiology. In the present study, we characterized the functional properties of the rat Na+–sulfate cotransporter NaS2 (rNaS2), determined its tissue distribution, and identified its gene (slc13a4) structure. Expression of rNaS2 protein in Xenopus oocytes led to a Na+-dependent transport of sulfate that was inhibited by phosphate, thiosulfate, tungstate, selenate, oxalate, and

Paul A. Dawson; Katrina J. Pirlo; Sarah E. Steane; Kim A. Nguyen; Karl Kunzelmann; Yu Ju Chien; Daniel Markovich

2005-01-01

339

Influence of capillary pressure on CO2 storage and monitoring Juan E. Santos, CONICET, Instituto del Gas y del Petroleo, Facultad Ingenieria, Universidad de Buenos Aires,  

E-print Network

del Gas y del Petr´oleo, Facultad Ingenier´ia, Universidad de Buenos Aires, Department of Mathematics´ias, Instituto del Gas y del Petr´oleo, Facultad Ingenier´ia, Universidad de Buenos Aires, Jos´e M. Carcione

Santos, Juan

340

Instantánea de los cánceres de cerebro y del sistema nervioso central  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre los cánceres de cerebro y del sistema nervioso central; así como ejemplos de actividades del NCI y adelantos en la investigación de estos tipos de cáncer.

341

78 FR 74008 - Amendment of Class E Airspace; Del Rio, TX  

Federal Register 2010, 2011, 2012, 2013, 2014

...controlled airspace at Laughlin AFB, Del Rio, TX. Environmental Review The...extension. * * * * * ASW TX E3 Del Rio, TX [Amended] Del Rio, Laughlin AFB, TX (Lat. 29...Fort Worth, Texas, on November 25, 2013. David P. Medina,...

2013-12-10

342

Conductivity of Zr-doped Na/sub 3/PO/sub 4/ : a new Na/sup +/ ion conductor  

SciTech Connect

Na/sub 3/PO/sub 4/ forms an extensive range of solid solutions with the replacement mechanism, 4Na/sup +/ in equilibrium Zr/sup 4 +/ and formula Na /sub 3-4x/ Zr /sub x/ PO/sub 4/: 0 < x < 0.20. With increasing x, the conductivity increases markedly and passes through a maximum at x approx. = 0.13 with a value of 2.5 x 10/sup -2/ ohm/sup -1/cm/sup -1/ at 300/sup 0/C. The solid solutions are thermodynamically stable, easily prepared and sinter into dense ceramics at about 1000/sup 0/C.

Milne, S.J.; West, A.R.

1984-06-01

343

La formación del Partido Conservador: la fusión conservadora  

Microsoft Academic Search

Aunque la Restauración, en cuanto a su historia política, es un período muy agraciado por lo que a atención historiográfica se refiere, todavía algunos aspectos del período están bajo el dominio de lugares comunes discutibles. Uno de ellos es la formación del Partido Conservador. En este artículo se sostiene que la fuerza formada por Antonio Cánovas, si bien hunde sus

Fidel Gómez Ochoa

2003-01-01

344

Vida Arti cial: Estudio y an alisis del programa SWARM  

E-print Network

Jim#19;enez Introducci#19;on En este libro se realiza un estudio, a nivel introductorio, del campo de descubrir aplicaciones en una rama fundamental del citado campo: la de los Mundos Arti#12;ciales. El texto, y que proporcionaron aut#19;enticos hitos en este campo. A continuaci#19;on, se presenta el programa

Jiménez, Mario de J. Pérez

345

El sector industrial del Tolima: aproximación histórica, estructura y dinámica  

Microsoft Academic Search

En virtud de las exenciones tributarias y arancelarias que dispuso el gobierno con el fin de reactivar la economía de la zona afectada por la erupción del volcán-nevado del Ruiz en 1985, la industria tolimense experimentó un período de auge entre 1990 y 1995, durante el cual creció la base industrial y se logró cierto grado de diversificación; sin embargo,

Alvaro Augusto Campos Martínez

2004-01-01

346

Calidad del aire interior y salud en las viviendas  

E-print Network

Calidad del aire interior y salud en las viviendas temporales de FEMA A los residentes de los tráileres Los Centros para el Control y la Prevención de Enfermedades (CDC) responden a las preocupa ciones que usted pueda tener sobre la calidad del aire y el formaldehído en los tráileres de FEMA. Usted

347

Decoding F508del misfolding in cystic fibrosis.  

PubMed

The functional deficiency of the cystic fibrosis transmembrane conductance regulator (CFTR), a plasma membrane chloride channel, leads to the development of cystic fibrosis. The deletion of a phenylalanine at residue 508 (F508del) is the most common cause of CFTR misfolding leading to the disease. The F508del misfolding originates in the first nucleotide-binding domain (NBD1), which induces a global conformational change in CFTR through NBD1's interactions with other domains. Such global misfolding produces a mutant chloride channel that is impaired in exocytic trafficking, peripheral stability, and channel gating. The nature and atomic details of F508del misfolding have been subject to extensive research during the past decade. Current data support a central role for NBD1 in F508del misfolding and rescue. Many cis-acting NBD1 second-site mutations rescue F508del misfolding in the context of full-length CFTR. While some of these mutations appear to specifically counteract the F508del-induced misfolding, others release certain inherent conformational constraints of the human wild-type CFTR. Several small-molecule correctors were recently found to act on key interdomain interfaces of F508del CFTR. Potential rational approaches have been proposed in an attempt to develop highly effective small molecule modulators that improve the cell surface functional expression of F508del CFTR. PMID:24970227

Wang, Xiaodong Robert; Li, Chenglong

2014-01-01

348

María Asunción Requena: Éxito e historia del teatro  

E-print Network

brujos y del futuro puente a construir; de las mujeres casaderas y de aquellas cuyos maridos partieron a la Patagonia. También hay sahumerios, huso y lana. ( Las Ultimas Noticias. 29 de octubre, 1989, p. 32) En junio del 89, Eduardo Guerrero...

Villegas, Juan

1995-04-01

349

> IRD/J. Orempuller Recursos y pilotaje del instituto  

E-print Network

44 45 s s s > © IRD/J. Orempuller #12;Recursos y pilotaje del instituto s Los medios financieros 46 disfrutado del apoyo de una importante movili- zación de los recursos financieros y de los medios humanos su patrimonio inmobilia- rio e invirtiendo en equipos científicos. medios financieros E L PRESUPUESTO

350

UNIVERSIDAD NACIONAL AUTNOMA DE MXICO Datos del plan de estudio  

E-print Network

Taekwondo Dirigido a: Entrenadores de la DGADyR, Comunidad Universitaria y Público General Síntesis o descripción breve: El curso le permite al interesado explicar el desarrollo histórico del taekwondo tanto en su país de origen, como en México, aplicar las diferentes técnicas del taekwondo para establecer la

Islas, León

351

ON THE MOTIVE OF A QUOTIENT VARIETY SEBASTIAN DEL BA ~  

E-print Network

ON THE MOTIVE OF A QUOTIENT VARIETY SEBASTIAN DEL BA ~ NO ROLLIN AND VICENTE NAVARRO AZNAR En with the realization functors and Chow groups. Recently, in the case char k = 0, Guill'en and Navarro Aznar have given. DEL BA ~ NO ROLLIN AND V. NAVARRO AZNAR group, K 0 M k , these decompositions were considered by Denef

Politècnica de Catalunya, Universitat

352

Analisi termica per la valutazione del danno negli acciai  

Microsoft Academic Search

RIASSUNTO. Sulla base di una metodologia consolidata, proposta in (26), per la definizione dell'intera curva di fatica di acciai mediante analisi termografica viene indicata una procedura per la valutazione del danno. Partendo dall'osservazione di base che ogni componente caricato dinamicamente, al di sopra del proprio limite di fatica, mostra un aumento di temperatura tanto più alto quanto più alto è

Antonino Risitano; Giacomo Risitano

2010-01-01

353

Impacto de las regalías petroleras en el Departamento del Meta  

Microsoft Academic Search

El departamento del Meta extrae petróleo crudo desde el año 1976, ubicándose, en la actualidad, entre los tres mayores productores del país. En consecuencia, con la influencia de su producción y las regalías, que han elevado el PIB departamental y fortalecido sus finanzas públicas, deben garantizarse amplías oportunidades de inversión, tanto pública como privada. El objetivo de este estudio es,

Germán Humberto Hernández Leal

2004-01-01

354

Inversiones en servicios públicos y dinámica del espacio urbano  

Microsoft Academic Search

El estudio de los servicios públicos constituye un campo en el que pueden examinarse la forma como la población satisface sus necesidades, los problemas y conflictos que se generan en el modo de producción, distribución y consumo, la relación entre el rol del Estado y las inversiones privadas en la satisfacción de esas necesidades y la construcción del espacio urbano.

Silvia Beatriz Grippo; Stella Maris Visciarelli

2007-01-01

355

Pastoral del Nino: Bringing the Abundant Life to Paraguayan Children  

ERIC Educational Resources Information Center

Pastoral del Nino is transforming children's lives in rural Paraguay. Part of Pastoral Social (Catholic Social Services), Pastoral del Nino's primary focus is to bring "vida en abundancia" (the abundant life) to families by ensuring that mothers survive childbirth and children reach their first birthdays. In addition, the organization promotes…

Austin, Ann Berghout; Aquino, Cyle; Burro, Elizabeth

2007-01-01

356

El comercio internacional en Colombia: una perspectiva diferente del TLC  

Microsoft Academic Search

La nueva teoría del comercio internacional deja de lado las diferencias entre los países en cuanto a recursos y se enfoca en las decisiones de los empresarios para presentar una visión alternativa de las implicaciones de la firma del Tratado de libre Comercio. La nueva teoría pone énfasis en la heterogeneidad de las empresas, en la relevancia de la productividad

Jan Ter Wengel; Luz Karine Ardila; Beatriz Ferreira Villegas; Luís Miguel Suárez Cruz

2007-01-01

357

EL COMERCIO INTERNACIONAL DE MÉXICO: ANTES Y DESPUÉS DEL TLCAN  

Microsoft Academic Search

El TLCAN trajo a México un alto pero breve crecimiento económico en sus primeros años de aplicación. En el pasado la economía y el comercio internacional del país estaba cimentado sobre la venta del petróleo crudo, teniendo una estabilidad importante en él, hasta el declive de sus precio en 1986, hoy en día el TLCAN a provocado un incremento sorprendente

Juan Antonio Herrera Izaguirre; Luis Hernán Lope Díaz; Alma Janeth Badillo Santes; Ramiro Aurelio Escobedo Carreón

2012-01-01

358

Conceptos fundamentales del desarrollo de proveedores (Caso de negocios 13)  

Microsoft Academic Search

El desarrollo de proveedores es una actividad que enriquece la gestión de la cadena de suministro, dotándola de mayor valor a través del aporte mutuo entre empresas clientes y subcontratistas. Este aporte incluye nuevas tecnologías, know-how, herramientas de la calidad y organización del trabajo, además de negociaciones sobre la política de precios, entre otros temas. En este trabajo presentamos sus

Enrique Yacuzzi

2012-01-01

359

[Escribir texto] DOBLE GRADO INGENIERA INFORMTICA -INGENIERA DEL SOFTWARE  

E-print Network

Desarrollo de Aplicaciones Web AIII 006 EAS Evolución y Adaptación del Software AIII 006 IA Inteligencia[Escribir texto] DOBLE GRADO INGENIERÍA INFORMÁTICA - INGENIERÍA DEL SOFTWARE Coordinador Informática - Ingeniería de Software 1er Semestre (Aulario III - Aula 002) Claves y profesores Clave

Rey Juan Carlos, Universidad

360

Reactions of NaCl with gaseous SO3, SO2, and O2  

NASA Technical Reports Server (NTRS)

Hot corrosion of gas turbine engine components involves deposits of Na2SO4 which are produced by reactions between NaCl and oxides of sulfur. For the present investigation, NaCl single crystals were exposed at 100 to 850 C to gaseous mixtures of SO3, SO2, and O2. The products formed during this exposure depend, primarily, on the temperatures. The four product films were: NaCl-SO3; Na2S2O7; Na2SO4; and NaCl-Na2SO4. The kinetics of the reactions were measured.

Fielder, W. L.; Stearns, C. A.; Kohl, F. J.

1984-01-01

361

Reactions of NaCl with Gaseous SO3, SO2, and O2  

NASA Technical Reports Server (NTRS)

Hot corrosion of gas turbine engine components involves deposits of Na2SO4 which are produced by reactions between NaCl and oxides of sulfur. For the present investigation, NaCl single crystals were exposed at 100 to 850 C to gaseous mixtures of SO3, SO2, and O2. The products formed during this exposure depend, primarily, on the temperatures. The four product films were: NaCl-SO3; Na2S2O7; Na2SO4; and NaCl-Na2SO4. The kinetics of the reactions were measured.

Fielder, W. L.; Stearns, C. A.; Kohl, F. J.

1983-01-01

362

O, Na, Ba and Eu abundance patterns in open clusters  

E-print Network

Open clusters are historically regarded as single-aged stellar populations representative of star formation within the Galactic disk. Recent literature has questioned this view, based on discrepant Na abundances relative to the field, and concerns about the longevity of bound clusters contributing to a selection bias: perhaps long-lived open clusters are chemically different to the star formation events that contributed to the Galactic disk. We explore a large sample of high resolution Na, O, Ba & Eu abundances from the literature, homogenized as much as reasonable including accounting for NLTE effects, variations in analysis and choice of spectral lines. Compared to a template globular cluster and representative field stars, we find no significant abundance trends, confirming that the process producing the Na-O anti-correlation in globular clusters is not present in open clusters. Furthermore, previously reported Na-enhancement of open clusters is found to be an artefact of NLTE effects, with the open cl...

MacLean, B T; Lattanzio, J

2014-01-01

363

ON RACK COHOMOLOGY P. ETINGOF & M. GRA"NA  

E-print Network

ON RACK COHOMOLOGY P. ETINGOF & M. GRA"NA Abstract.We prove that the lower bounds for Betti numbers of the rack, qu-theoretical interpretation of t* *he second cohomology group for racks. 1.Introduction

Graña, Matías

364

Degradation Of Carbon/Phenolic Composites By NaOH  

NASA Technical Reports Server (NTRS)

Effects of sodium hydroxide contamination level on physical and chemical properties of phenolic resin and carbon/phenolic composites described in report. NaOH degrades both carbon and phenolic components of carbon/phenolic laminates.

King, H. M.; Semmel, M. L.; Goldberg, B. E.; Clinton, Raymond G., Jr.

1989-01-01

365

NaIrO 3—A pentavalent post-perovskite  

NASA Astrophysics Data System (ADS)

Sodium iridium (V) oxide, NaIrO 3, was synthesized by a high pressure solid state method and recovered to ambient conditions. It is found to be isostructural with CaIrO 3, the much-studied structural analog of the high-pressure post-perovskite phase of MgSiO 3. Among the oxide post-perovskites, NaIrO 3 is the first example with a pentavalent cation. The structure consists of layers of corner- and edge-sharing IrO 6 octahedra separated by layers of NaO 8 bicapped trigonal prisms. NaIrO 3 shows no magnetic ordering and resistivity measurements show non-metallic behavior. The crystal structure, electrical and magnetic properties are discussed and compared to known post-perovskites and pentavalent perovskite metal oxides.

Bremholm, M.; Dutton, S. E.; Stephens, P. W.; Cava, R. J.

2011-03-01

366

Tb/Na tobermorite: Thermal behaviour and high temperature products  

SciTech Connect

By heating a sample of Tb/Na tobermorite we obtained a phase which was identified through its X-ray diffraction (XRD) pattern, as terbium silicate apatite. Subsequently this compound has been directly prepared by solid state reaction and we carried out a structural refinement from XRD data in space group P6{sub 3}/m obtaining cell parameters a=9.39199(4) A and c=6.84041(5) A. Terbium silicate apatite heated in melted NaF led to Tb{sub 4}O{sub 7} crystals. - Graphical Abstract: By heating over 900 deg. C Tb/Na tobermorite a terbium silicate apatite was obtained. The same product has been independently prepared and structurally characterized from powder diffraction data. Attempts of crystallizing terbium silicate apatite from melted NaF led to Tb{sub 4}O{sub 7} crystals.

Garra, Walter [Dipartimento di Chimica e Chimica Industriale, Universita di Pisa, via Risorgimento, 35, 56126 Pisa (Italy); Marchetti, Fabio, E-mail: fama@dcci.unipi.i [Dipartimento di Chimica e Chimica Industriale, Universita di Pisa, via Risorgimento, 35, 56126 Pisa (Italy); Merlino, Stefano [Dipartimento di Scienze della Terra, Universita di Pisa, via S. Maria, 53, 56126 Pisa (Italy)

2009-06-15

367

Triple-point wetting of Xe on NaF  

NASA Astrophysics Data System (ADS)

We have measured high-precision adsorption isotherms of Xe on NaF by using a torsional oscillator microbalance. In contrast to theoretical predictions, we find that this system undergoes triple-point wetting.

Bruschi, L.; Mistura, G.

1998-07-01

368

Nac onal~na akadem nauk Ukra ni KONDENSOVANIH  

E-print Network

nn . I.M.Mpiglod, A.M.Gaqkeviq Anotac . Na osnovi metodu nepivnova nogo statistiqnogo Zuba- p va dl dovil~nogo nabopu dinamiqnih zminnih otpimani zagal~ni pivn nn teopi lini no pelaksaci ppostih pidin

369

NaIrO3—A Pentavalent Post-perovskite  

SciTech Connect

Sodium iridium (V) oxide, NaIrO{sub 3}, was synthesized by a high pressure solid state method and recovered to ambient conditions. It is found to be isostructural with CaIrO{sub 3}, the much-studied structural analog of the high-pressure post-perovskite phase of MgSiO{sub 3}. Among the oxide post-perovskites, NaIrO{sub 3} is the first example with a pentavalent cation. The structure consists of layers of corner- and edge-sharing IrO{sub 6} octahedra separated by layers of NaO{sub 8} bicapped trigonal prisms. NaIrO{sub 3} shows no magnetic ordering and resistivity measurements show non-metallic behavior. The crystal structure, electrical and magnetic properties are discussed and compared to known post-perovskites and pentavalent perovskite metal oxides.

M Bremholm; S Dutton; P Stephens; R Cava

2011-12-31

370

Nuclear spin-lattice relaxation in the sodium anion, Na -  

NASA Astrophysics Data System (ADS)

We report direct measurements of nuclear spin-lattice relaxation times (T1n) for the sodium anion, Na-, in solutions containing both sodium and a heavier alkali metal in 1,4,7,10-tetraoxacyclododecane (12-crown-4, 12C4). Nuclear spin-lattice relaxation in Na- is found to be essentially independent of the alkali counterion and to depend only weakly upon the concentration of sodide ion in solution. The temperature dependence of T1n for Na- was used to determine an activation energy for the processes responsible for spin relaxation. The results are consistent with a dominant, but very inefficient, quadrupolar relaxation mechanism which involves the modulation of the electric field gradient at Na- via the reorientation and/or translational motion of surrounding 12C4 molecules in the liquid. Furthermore, we find that solvation of Na- in 12C4 as well described by a model in which there is neither preferential orientation of 12C4 molecules nor a clearly identifiable first solvation shell around the sodide ion. Consistent with this description, the activation energies for the processes responsible for spin-lattice relaxation in Na- are close to those observed for the processes causing 1H and 13C relaxation in the neat liquid crown. We outline two methods, which take into account electron-electron correlation effects, for determining the Sternheimer antishielding factor ?2 for the sodium anion. The most realistic estimate for ?2 (-14.98) is used to calculate the NMR linewidth for Na- when it is associated with an uncomplexed (unsolvated) sodium cation and also in the contact and solvent-separated Na+-Na- ion pairs. A rms value of 0.03 MHz for the quadrupole coupling constant (e2qQ/?) of Na- in 12C4 solutions is deduced. We conclude that Na- in these solutions suffers only minor perturbations on its gas-phase electronic structure; neither does it exist as part of a contact or solvent-separated ion pair. It appears that the sodide ion represents the closest realization of a gas-like ionic moiety in solution.

Holton, Dolores M.; Ellaboudy, Ahmed; Pyper, Nicholas C.; Edwards, Peter P.

1986-02-01

371

Single Na+ channel currents observed in cultured rat muscle cells  

Microsoft Academic Search

The voltage- and time-dependent conductance of membrane Na+ channels is responsible for the propagation of action potentials in nerve and muscle cells. In voltage-step-clamp experiments on neurone preparations containing 104-107 Na+ channels the membrane conductance shows smooth variations in time, but analysis of fluctuations1,2 and other evidence3 suggest that the underlying single-channel conductance changes are stochastic, rapid transitions between `closed'

Frederick J. Sigworth; Erwin Neher

1980-01-01

372

Substructure of membrane-bound Na + ?K + ATPase protein  

Microsoft Academic Search

Purified membrane-bound Na+-K+-ATPase from rat kidney outer medulla was studied by freeze-fracturing, by freeze-etching and by negative staining. Freeze-fracturing of purified Na+-K+-ATPase membranes shows intramembraneous particles with a diameter of about 100 Å. The frequency of these intramembraneous particles — as estimated from the particle densities on the two fracture faces — lies between 4700 and 5600 particles per µm2.

W. Haase; H. Koepsell

1979-01-01

373

Broad-band structured fluorescence from NaI  

Microsoft Academic Search

The emission spectrum of a molecular beam of NaI has been measured following excitation by the 248 nm KrF line of an excimer laser. The fluorescence structure, and the lifetime (17±2 ns), indicate the presence of a bound upper state not previously characterized. We identify this state as correlating with Na(3 2P)+I(5 2P3\\/2) atoms. Through numerical simulation using a Morse

R. D. Bower; P. Chevrier; P. Das; H. J. Foth; J. C. Polanyi; M. G. Prisant; J. P. Visticot

1988-01-01

374

Evolution of Na(+) and H(+) bioenergetics in methanogenic archaea.  

PubMed

Methanogenic archaea live at the thermodynamic limit of life and use sophisticated mechanisms for ATP synthesis and energy coupling. The group of methanogens without cytochromes use an Na(+) current across the membrane for ATP synthesis, whereas the cytochrome-containing methanogens have additional coupling sites that also translocate protons. The ATP synthase in this group is promiscuous and uses Na(+) and H(+) simultaneously. PMID:23356322

Schlegel, Katharina; Müller, Volker

2013-02-01

375

Comparative effects of chemical amendments on salt and NA leaching  

Microsoft Academic Search

Efficiency of sodic soil reclamation is thought to vary with types of chemicals used. This study examined the effects of five inorganic (H2SO4, CaCl2 · 2H2O, CaSO4 · 2H2O, FeSO4, Al2(SO4)3) and two organic compounds (polyacrylamide, and trihydroxy glutaric acid) on the rate and the extent of salt and Na leaching in moderately Na-affected saline soils: Saneli silty clay loam

S. Miyamoto; C. Enriquez

1990-01-01

376

Effect of pH on Na induced Ca deficiency  

Microsoft Academic Search

Although it is well known that high Na concentrations induce Ca deficiency in acidic conditions, the effect of high pH on\\u000a this competitive mechanism is not so well understood. The effect of Ca activity ratio (CAR) and pH on the Ca uptake of mungbeans\\u000a (Vigna radiata (L.) Wilczek cv. Emerald) and Rhodes grass (Chloris gayana cv. Pioneer) in Na dominated

Peter M. Kopittke; Neal W. Menzies

2005-01-01

377

Resonance reaction rate of 21Na(p,?)22Mg  

Microsoft Academic Search

By using the new Coulomb screening model and most recent experimental results, this paper calculates the resonance reaction rates of 21Na(p,?)22Mg. The derived result shows that the effect of electron screening on resonant reaction is prominent in astrophysical interesting temperature range. In conjunction with the experimental results, the recommended rates of21Na(p,?)22Mg would increase at least 10%, which undoubtedly affect the

Liu Hong-Lin; Liu Men-Quan; Liu Jing-Jing; Luo Zhi-Quan

2007-01-01

378

Wall relaxation rates for an optically pumped Na vapor  

NASA Astrophysics Data System (ADS)

The wall relaxation rates for an optically pumped Na vapor have been measured for a variety of wall surfaces. We find that fluorocarbon rubber (Fluorel or Viton) at a temperature of 250°C has a relaxation rate that corresponds on the average to 10-15 bounces before depolarization occurs. A surface with a relaxation rate this small is potentially very important for use in the polarized Na vapor charge exchange target used in the optically pumped polarized H - ion source.

Swenson, D. R.; Anderson, L. W.

1985-08-01

379

Status and plans of the NA61/SHINE physics program  

SciTech Connect

One of the NA61/SHINE experiment's goals is to discover the critical point of strongly interacting matter and study the properties of the onset of deconfinement. This is to be achieved by performing a two-dimensional phase diagram (T- Micro-Sign {sub B}) scan-measuring hadron production in collisions of various beam particles and targets at various beam energies. NA61/SHINE also collects data for the T2K experiment, which are just about to be published.

Czopowicz, T., E-mail: Tobiasz.Roman.Czopowicz@cern.ch [Warsaw University of Technology, Faculty of Physics (Poland)

2012-06-15

380

Na + Xe collisions in the presence of two nonresonant lasers  

NASA Technical Reports Server (NTRS)

Na+Xe collisions in the presence of two distinct laser fields (rhodamine 110 and Nd:glass) are investigated with reference to the response to nonresonant radiation of alkali metals collisionally perturbed by a buffer gas. It is found that the excited Na-asterisk (4s)+Xe state is produced with a measurable cross section due to two-photon absorption with field intensities as low as 10 MW/sq cm.

De Vries, P. L.; Chang, C. H.; George, T. F.; Laskowski, B.; Stallcop, J. R.

1980-01-01

381

Kinetics of the Reverse Mode of the Na + \\/Glucose Cotransporter  

Microsoft Academic Search

This study investigates the reverse mode of the Na+\\/glucose cotransporter (SGLT1). In giant excised inside-out membrane patches from Xenopus laevis oocytes expressing rabbit SGLT1, application of a-methyl-D-glucopyranoside (aMDG) to the cytoplasmic solution induced an outward current from cytosolic to external membrane surface. The outward current was Na+- and sugar-dependent, and was blocked by phlorizin, a specific inhibitor of SGLT1. The

S. Eskandari; E. M. Wright; D. D. F. Loo

2005-01-01

382

Expression of epithelial Na channels in Xenopus oocytes  

Microsoft Academic Search

Epithelial Na channel activity was expressed in oocytes from Xenopus laev\\/s after injection of mRNA from A6 cells, derived from Xenopus kidney. Poly A(+) RNA was extracted from confluent cell monolayers grown on either plastic or permeable supports. 1-50 ng RNA was injected into stage 5-6 oocytes. Na channel activity was assayed as amiloride-sensitive current (Isa) under voltage-clamp condi- tions

LAWRENCE G. PALMER; IRENE CORTHESY-THEULAZ; HANS-PETER GAEGGELER; JEAN-PIERRE KRAEHENBUHL; BERNARD ROSSIER

1990-01-01

383

Electrogenic Na + \\/K + -transport in human endothelial cells  

Microsoft Academic Search

Na+\\/K+ pump currents were measured in endothelial cells from human umbilical cord vein using the whole-cell or nystatin-perforated-patch-clamp technique combined with intracellular calcium concentration ([Ca2+]i) measurements with Fura-2\\/AM. Loading endothelial cells through the patch pipette with 40 mmol\\/l [Na+] did not induce significant changes of [Ca2+]i. Superfusing the cells with K+-free solutions also did not significantly affect [Ca2+]i. Reapplication of

Masahiro Oike; Guy Droogmans; Rik Casteels; Bernd Nilius

1993-01-01

384

Na-caseinate/oil/water systems: emulsion morphology diagrams.  

PubMed

The concentrated (dispersed phase 50-70 wt%) composition space of Na-caseinate, a family of milk proteins, stabilised emulsions was investigated for three different oils: soybean oil, palm olein and tetradecane with pH 6.8 phosphate buffer continuous phase. The variation of emulsion stability and microstructure were explored using static light scattering, diffusion nuclear magnetic resonance, cryo-scanning electron microscopy, rheology and the time varying macroscopic phase separation of the emulsions. For soybean oil and palm olein a rich diversity of emulsion microstructures and stabilities are realised. Five emulsion domains, each having a different microstructure and macroscopic stability have been identified within the composition space probed. For the lowest concentrations of emulsifier bridging flocculation is evident and emulsions are of low stability. Increasing Na-caseinate concentration leads to an increased stability and the existence of distinct individual oil droplets, visualised using cryo-scanning electron microscopy. Further increases in Na-caseinate concentration reduce emulsion stability due to depletion flocculation. Na-caseinate self-assembly is then initiated. At sufficiently high Na-caseinate and/or oil concentrations the continuous phase of the emulsion is a three-dimensional protein network and emulsion stability is again enhanced. At the limits of the emulsion composition space a gel-like paste is formed. The diversity of emulsion microstructure is reduced when tetradecane is the discrete phase. Na-caseinate self-assembly is limited and there is no evidence for formation of a protein network. PMID:22709624

Tan, Hui Lin; McGrath, Kathryn M

2012-09-01

385

Regulation of Na,K-ATPase during acute lung injury.  

PubMed

A hallmark of acute lung injury is the accumulation of a protein rich edema which impairs gas exchange and leads to hypoxemia. The resolution of lung edema is effected by active sodium transport, mostly contributed by apical Na(+) channels and the basolateral located Na,K-ATPase. It has been reported that the decrease of Na,K-ATPase function seen during lung injury is due to its endocytosis from the cell plasma membrane into intracellular pools. In alveolar epithelial cells exposed to severe hypoxia, we have reported that increased production of mitochondrial reactive oxygen species leads to Na,K-ATPase endocytosis and degradation. We found that this regulated process follows what is referred as the Phosphorylation-Ubiquitination-Recognition-Endocytosis-Degradation (PURED) pathway. Cells exposed to hypoxia generate reactive oxygen species which activate PKC zeta which in turn phosphorylates the Na,K-ATPase at the Ser18 residue in the N-terminus of the alpha1-subunit leading the ubiquitination of any of the four lysines (K16, K17, K19, K20) adjacent to the Ser18 residue. This process promotes the alpha1-subunit recognition by the mu2 subunit of the adaptor protein-2 and its endocytosis trough a clathrin dependent mechanism. Finally, the ubiquitinated Na,K-ATPase undergoes degradation via a lysosome/proteasome dependent mechanism. PMID:17972021

Lecuona, Emilia; Trejo, Humberto E; Sznajder, Jacob I

2007-12-01

386

Band gap engineering for graphene by using Na+ ions  

NASA Astrophysics Data System (ADS)

Despite the noble electronic properties of graphene, its industrial application has been hindered mainly by the absence of a stable means of producing a band gap at the Dirac point (DP). We report a new route to open a band gap (Eg) at DP in a controlled way by depositing positively charged Na+ ions on single layer graphene formed on 6H-SiC(0001) surface. The doping of low energy Na+ ions is found to deplete the ?* band of graphene above the DP, and simultaneously shift the DP downward away from Fermi energy indicating the opening of Eg. The band gap increases with increasing Na+ coverage with a maximum E g ? 0.70 eV. Our core-level data, C 1s, Na 2p, and Si 2p, consistently suggest that Na+ ions do not intercalate through graphene, but produce a significant charge asymmetry among the carbon atoms of graphene to cause the opening of a band gap. We thus provide a reliable way of producing and tuning the band gap of graphene by using Na+ ions, which may play a vital role in utilizing graphene in future nano-electronic devices.

Sung, S. J.; Lee, P. R.; Kim, J. G.; Ryu, M. T.; Park, H. M.; Chung, J. W.

2014-08-01

387

Valoración Económica y Ambiental Aplicada a Casos del Manejo de la Calidad del Aire y Control de la Contaminación  

Microsoft Academic Search

Este documento fue comisionado por la Red de Medio Ambiente del Diálogo Regional de Política para la III Reunión Hemisférica celebrada los días 9 y 10 de marzo de 2004. Durante las últimas décadas se han establecido derechos y obligaciones ciudadanas; se han definido las funciones del Estado y de los organismos públicos responsables en materia ambiental; se han realizado

Luis A. Cifuentes; Luis Rizzi; Héctor Jorquera; Javier Vergara

2004-01-01

388

El Instituto Nacional del Cáncer de EE. UU. y la República del Perú firman una Declaración de Intención  

Cancer.gov

El Instituto Nacional del Cáncer y la República del Perú firmaron una declaración de intención para compartir el interés en fomentar la investigación biomédica de oncología, basándose en la colaboración mutua de ambas entidades, así como el objetivo común de educar y capacitar la futura generación de científicos y clínicos en investigación oncológica.

389

IMPORTANCIA Y VIGENCIA DEL PENSAMIENTO DE EDGAR MORÍN EN LA COMPRENSIÓN DEL CONOCIMIENTO. UNA VISIÓN DESDE LA PSICOLOGÍA  

Microsoft Academic Search

El presente artículo pretende exponer los diferentes retos que presentan la educación y el aprendizaje del siglo XXI mediante la exposición de las particularidades que presenta el conocimiento adquirido por el hombre a través de su historia. Se basa fundamentalmente en algunos planteamientos ofrecidos por Edgar Morín en su libro “Los siete saberes necesarios para la educación del futuro” ,

Mildreth Larquin Castillo

2011-01-01

390

Notas para el estudio del cambio social a comienzos del quinto ciclo de Kondratiev. Un marco teórico  

Microsoft Academic Search

El alza de los precios del pétroleo acontecida en 1973 puso fin a la más reciente fase de expansión del excepcional ciclo de crecimiento iniciado después de la segunda Guerra Mundial. Luego de un periodo tan largo e impresionante de bonanza -la producción industrial de los países de la OCDE se quintuplicó por ejemplo entre 1947 y 1973- era natural

Mauricio Rojas

1991-01-01

391

La metodologia de la valoracion contingente en la evaluacion de proyectos ambientales : el caso del saneamiento del Rio Medellin  

Microsoft Academic Search

Como consecuencia del crecimiento de las ciudades, se hace cada vez más sentida la necesidad de desarrollar proyectos de carácter ambiental que subsanen el efecto negativo del urbanismo y las grandes concentraciones poblacionales. Tal es el caso de los rellenos sanitarios y sistemas de alcantarillado y tratamiento de aguas residuales, entre otros. Sin embargo, los problemas de contaminación y saneamiento,

Fredy Zuleta D

1994-01-01

392

Simultaneous optical excitation of Na electronic and CF{sub 4} vibrational modes in Na+CF{sub 4} collisions  

SciTech Connect

We report on the ultraviolet excitation of Na(3s)+CF{sub 4} collision pairs in a crossed molecular beam experiment. We observe Na(3d) collision products originating from the process Na(3s)+CF{sub 4}({nu}{sub 3}=0)+h{nu}{yields}Na(3d)+CF{sub 4}({nu}{sub 3}=1). The spectral intensity distribution of the collision products and the prevailing small angle scattering confirm a previously proposed long range dipole-dipole mechanism. We report velocity-resolved spectra and a comparison to preliminary numerical results based on collisional broadening theory. Polarization experiments suggest future potential for the observation of collision geometries.

Alekseev, V. A. [Department of Physics, St. Petersburg State University, Peterhof 198504 (Russian Federation); Grosser, J.; Hoffmann, O. [Institut fuer Gravitationsphysik, Leibniz Universitaet Hannover, 30167 Hannover (Germany); Rebentrost, F. [Max-Planck-Institut fuer Quantenoptik, 85748 Garching (Germany)

2008-11-28

393

NaCl nanodroplet on NaCl(1 0 0) at the melting point  

NASA Astrophysics Data System (ADS)

The self-wetting properties of ionic crystal surfaces are studied, using NaCl(1 0 0) as a prototype case. The anomalously large contact angle measured long ago by Mutaftschiev [Surf. Sci. 47 (1975) 723; J. Cryst. Growth 182 (1997) 205] is well reproduced by realistic molecular dynamics simulations. Based on these results, and on independent determinations of the liquid-vapor ( ?LV) and the solid-vapor interface free energy ( ?SV) [Zykova-Timan et al. to be published], an estimate of the solid-liquid interface free energy ( ?SL) is extracted. The solid-vapor surface free energy turns out to be small and similar to the liquid-vapor one, providing a direct thermodynamic explanation of the reduced wetting ability of the ionic melt.

Zykova-Timan, T.; Tartaglino, U.; Ceresoli, D.; Sekkal-Zaoui, W.; Tosatti, E.

2004-09-01

394

Salt resistance of chickpea genotypes in solutions salinized with NaCl or Na 2 SO 4  

Microsoft Academic Search

Summary  To assess the potential for developing a salt resistant cultivar of chickpea (Cicer arietinum L.) 160 genotypes were screened for percent survival after 9 weeks in greenhouse solution cultures, with 50 mM NaCl or 25 mM Na2SO4. All plants grew well in the sulfate treatment but only cv. L-550 survived the chloride treatment. Salt damage appeared and\\u000a developed slowly.\\u000a \\u000a To

D. J. Lauter; D. N. Munns

1986-01-01

395

Na(+) transport, and the E(1)P-E(2)P conformational transition of the Na(+)/K(+)-ATPase.  

PubMed Central

We have used admittance analysis together with the black lipid membrane technique to analyze electrogenic reactions within the Na(+) branch of the reaction cycle of the Na(+)/K(+)-ATPase. ATP release by flash photolysis of caged ATP induced changes in the admittance of the compound membrane system that are associated with partial reactions of the Na(+)/K(+)-ATPase. Frequency spectra and the Na(+) dependence of the capacitive signal are consistent with an electrogenic or electroneutral E(1)P <--> E(2)P conformational transition which is rate limiting for a faster electrogenic Na(+) dissociation reaction. We determine the relaxation rate of the rate-limiting reaction and the equilibrium constants for both reactions at pH 6.2-8.5. The relaxation rate has a maximum value at pH 7.4 (approximately 320 s(-1)), which drops to acidic (approximately 190 s(-1)) and basic (approximately 110 s(-1)) pH. The E(1)P <--> E(2)P equilibrium is approximately at a midpoint position at pH 6.2 (equilibrium constant approximately 0.8) but moves more to the E(1)P side at basic pH 8.5 (equilibrium constant approximately 0.4). The Na(+) affinity at the extracellular binding site decreases from approximately 900 mM at pH 6.2 to approximately 200 mM at pH 8.5. The results suggest that during Na(+) transport the free energy supplied by the hydrolysis of ATP is mainly used for the generation of a low-affinity extracellular Na(+) discharge site. Ionic strength and lyotropic anions both decrease the relaxation rate. However, while ionic strength does not change the position of the conformational equilibrium E(1)P <--> E(2)P, lyotropic anions shift it to E(1)P. PMID:11053130

Babes, A; Fendler, K

2000-01-01

396

[Na] and [K] dependence of the Na\\/K pump current-voltage relationship in guinea pig ventricular myocytes  

Microsoft Academic Search

Na\\/K pump current was determined between - 140 and +60 mV as steady-state, strophanthidin-sensitive, whole-cell current in guinea pig ventricular myocytes, voltage-clamped and internally dialyzed via wide-tipped pipettes. Solu- tions were designed to minimize all other components of membrane current. A device for exchanging the solution inside the pipette permitted investigation of Na\\/K pump current-voltage (I-V) relationships at several levels

MASAKAZU NAKAO; DAVID C. GADSBY

1989-01-01

397

La biomedicina del segle XXI: nous paradigmes i noves responsabilitats dels científics  

Microsoft Academic Search

Tal com s'inverteixen cada cop més recursos a tot el món en recerca biomèdica i en\\u000aciències de la salut, també evoluciona la tradicional confiança de la societat en el progrés\\u000acientífic. Creixen les demandes de participació, d'eficàcia, de més aplicabilitat i d'impacte\\u000asocial dels recursos públics dedicats a la recerca, mentre que la professió de científic encara\\u000aconserva una

Jordi Camí i Morell

2012-01-01

398

Targeting Voltage Gated Sodium Channels NaV1.7, NaV1.8, and NaV1.9 for Treatment of Pathological Cough  

PubMed Central

Recent advances in our understanding of voltage-gated sodium channels (NaVs) lead to the rational hypothesis that drugs capable of selective blockade of NaV subtypes may be a safe and effective strategy for the treatment of unwanted cough. Among the nine NaV subtypes (NaV1.1–NaV1.9), the afferent nerves involved in initiating cough, in common with nociceptive neurons in the somatosensory system, express mainly NaV1.7, NaV1.8, and NaV1.9. Although knowledge about the effect of selectively blocking these channels on the cough reflex is limited, their biophysical properties indicate that each may contribute to the hypertussive and allotussive state that typifies subacute and chronic nonproductive cough. PMID:24272479

Muroi, Yukiko

2015-01-01

399

The dynamic relationships between the three events that release individual Na+ ions from the Na+/K+-ATPase  

PubMed Central

Na+/K+ pumps move net charge through the cell membrane by mediating unequal exchange of intracellular Na+ and extracellular K+. Most charge moves during transitions that release Na+ to the cell exterior. When pumps are constrained to bind and release only Na+, a membrane voltage-step redistributes pumps among conformations with zero, one, two or three bound Na+, thereby transiently generating current. By applying rapid voltage steps to squid giant axons, we previously identified three components in such transient currents, with distinct relaxation speeds: fast (which nearly parallels the voltage-jump time course), medium speed (?m=0.2–0.5?ms) and slow (?s=1–10?ms). Here we show that these three components are tightly correlated, both in their magnitudes and in the time courses of their changes. The correlations reveal the dynamics of the conformational rearrangements that release three Na+ to the exterior (or sequester them into their binding sites) one at a time, in an obligatorily sequential manner. PMID:22334072

Gadsby, David C.; Bezanilla, Francisco; Rakowski, Robert F.; De Weer, Paul; Holmgren, Miguel

2012-01-01

400

The dynamic relationships between the three events that release individual Na? ions from the Na?/K?-ATPase.  

PubMed

Na(+)/K(+) pumps move net charge through the cell membrane by mediating unequal exchange of intracellular Na(+) and extracellular K(+). Most charge moves during transitions that release Na(+) to the cell exterior. When pumps are constrained to bind and release only Na(+), a membrane voltage-step redistributes pumps among conformations with zero, one, two or three bound Na(+), thereby transiently generating current. By applying rapid voltage steps to squid giant axons, we previously identified three components in such transient currents, with distinct relaxation speeds: fast (which nearly parallels the voltage-jump time course), medium speed (?(m)=0.2-0.5?ms) and slow (?(s)=1-10?ms). Here we show that these three components are tightly correlated, both in their magnitudes and in the time courses of their changes. The correlations reveal the dynamics of the conformational rearrangements that release three Na(+) to the exterior (or sequester them into their binding sites) one at a time, in an obligatorily sequential manner. PMID:22334072

Gadsby, David C; Bezanilla, Francisco; Rakowski, Robert F; De Weer, Paul; Holmgren, Miguel

2012-01-01

401

?3 subunit of Na,K ATPase regulates T cell activation with no involvement of Na,K ATPase activity.  

PubMed

Na,K ATPase plays an important role in the regulation of Na(+) and K(+) ions that are required for normal resting membrane potential and various cellular functions. Na,K ATPase is composed of two subunits, ? and ? subunits. Engagement of the ? subunit by an agonistic monoclonal antibody (mAb) P-3E10 inhibited T cell activation and induced the G0/G1 cell cycle arrest. In addition, mAb P-3E10 decreased CD25 expression. The mAb P-3E10, however, did not inhibit the proliferation of cell lines and the phagocytosis activity of phagocytes, and did not interfere with the Na,K ATPase activity. These results indicate that mAb P-3E10 reacts to the ? subunit and, as a consequence, brings about the regulation of the T cell activation without disturbing the Na,K pump activity. By sequential immunoprecipitation, we demonstrated the expression of the ?3 subunit free form apart from the ? subunit. In this study, we propose that the ?3 subunits of Na,K ATPase are expressed separately from the ? subunit, and play a role in regulation of the immune response. PMID:25678464

Chruewkamlow, Nuttapol; Pata, Supansa; Mahasongkram, Kodchakorn; Laopajon, Witida; Kasinrerk, Watchara; Chiampanichayakul, Sawitree

2015-05-01

402

A sodium calcium arsenate, NaCa(AsO(4)).  

PubMed

The title compound, NaCa(AsO(4)), was synthesized using a hydro-thermal method at 633-643?K. It has a dense structure composed of alternating layers of distorted [CaO(6)] octa-hedra and layers of [AsO(4)] tetra-hedra and distorted [NaO(6)] octa-hedra, stacked along the a axis. The As, Ca and two O atoms lie on the mirror plane at y = 1/4 (i.e. 4c), while the Na atom lies on an inversion centre (1/2, 1/2, 0) (i.e. 4b). Each distorted [CaO(6)] octa-hedron shares four equatorial common O vertices with four neighboring octa-hedra, forming a layer parallel to (100), whereas each distorted [NaO(6)] octa-hedron shares two opposite edges with two neighboring ones, forming a chain running along [010]. Each isolated [AsO(4)] tetra-hedron shares two edges with two different [NaO(6)] octa-hedra in one [NaO(6)] chain and a vertex with another chain. Simultaneously the above [AsO(4)] tetra-hedron located in a four-membered [CaO(6)] ring shares one edge of its base facet with one [CaO(6)] octa-hedron and three corners with three other [CaO(6)] octa-hedra of one [CaO(6)] layer, and the remaining apex is shared with another [CaO(6)] layer. [NaO(6)] octa-hedra and [CaO(6)] octa-hedra are linked to each other by sharing edges and vertices. PMID:22199467

Lin, Jinru; Sun, Wei; Mi, Jin-Xiao; Pan, Yuanming

2011-12-01

403

The Expression Pattern of the Na(+) Sensor, Na(X) in the Hydromineral Homeostatic Network: A Comparative Study between the Rat and Mouse.  

PubMed

The Scn7a gene encodes for the specific sodium channel Na(X), which is considered a primary determinant of sodium sensing in the brain. Only partial data exist describing the Na(X) distribution pattern and the cell types that express Na(X) in both the rat and mouse brain. To generate a global view of the sodium detection mechanisms in the two rodent brains, we combined Na(X) immunofluorescence with fluorescent cell markers to map and identify the Na(X)-expressing cell populations throughout the network involved in hydromineral homeostasis. Here, we designed an anti-Na(X) antibody targeting the interdomain 2-3 region of the Na(X) channel's ?-subunit. In both the rat and mouse, Na(X) immunostaining was colocalized with vimentin positive cells in the median eminence and with magnocellular neurons immunopositive for neurophysin associated with oxytocin or vasopressin in both the supraoptic and paraventricular nuclei. Na(X) immunostaining was also detected in neurons of the area postrema. In addition to this common Na(X) expression pattern, several differences in Na(X) immunostaining for certain structures and cell types were found between the rat and mouse. Na(X) was present in both NeuN and vimentin positive cells in the subfornical organ and the vascular organ of the lamina terminalis of the rat whereas Na(X) was only colocalized with vimentin positive cells in the mouse circumventricular organs. In addition, Na(X) immunostaining was specifically observed in NeuN immunopositive cells in the median preoptic nucleus of the rat. Overall, this study characterized the Na(X)-expressing cell types in the network controlling hydromineral homeostasis of the rat and mouse. Na(X) expression pattern was clearly different in the nuclei of the lamina terminalis of the rat and mouse, indicating that the mechanisms involved in systemic and central Na(+) sensing are specific to each rodent species. PMID:22833716

Nehmé, Benjamin; Henry, Mélaine; Mouginot, Didier; Drolet, Guy

2012-01-01

404

Identification of Nocobactin NA Biosynthetic Gene Clusters in Nocardia farcinica? §  

PubMed Central

We identified the biosynthetic gene clusters of the siderophore nocobactin NA. The nbt clusters, which were discovered as genes highly homologous to the mycobactin biosynthesis genes by the genomic sequencing of Nocardia farcinica IFM 10152, consist of 10 genes separately located at two genomic regions. The gene organization of the nbt clusters and the predicted functions of the nbt genes, particularly the cyclization and epimerization domains, were in good agreement with the chemical structure of nocobactin NA. Disruptions of the nbtA and nbtE genes, respectively, reduced and abolished the productivity of nocobactin NA. The heterologous expression of the nbtS gene revealed that this gene encoded a salicylate synthase. These results indicate that the nbt clusters are responsible for the biosynthesis of nocobactin NA. We also found putative IdeR-binding sequences upstream of the nbtA, -G, -H, -S, and -T genes, whose expression was more than 10-fold higher in the low-iron condition than in the high-iron condition. These results suggest that nbt genes are regulated coordinately by IdeR protein in an iron-dependent manner. The ?nbtE mutant was found to be impaired in cytotoxicity against J774A.1 cells, suggesting that nocobactin NA production is required for virulence of N. farcinica. PMID:21097631

Hoshino, Yasutaka; Chiba, Kazuhiro; Ishino, Keiko; Fukai, Toshio; Igarashi, Yasuhiro; Yazawa, Katsukiyo; Mikami, Yuzuru; Ishikawa, Jun

2011-01-01

405

Adenosine, type 1 receptors: role in proximal tubule Na+ reabsorption.  

PubMed

Adenosine type 1 receptor (A1 -AR) antagonists induce diuresis and natriuresis in experimental animals and humans. Much of this effect is due to inhibition of A1 -ARs in the proximal tubule, which is responsible for 60-70% of the reabsorption of filtered Na(+) and fluid. Intratubular application of receptor antagonists indicates that A1 -AR mediates a portion of Na(+) uptake in PT and PT cells, via multiple transport systems, including Na(+) /H(+) exchanger-3 (NHE3), Na(+) /PO4(-) co-transporter and Na(+) -dependent glucose transporter, SGLT. Renal microperfusion and recollection studies have shown that fluid reabsorption is reduced by A1 -AR antagonists and is lower in A1 -AR KO mice, compared to WT mice. Absolute proximal reabsorption (APR) measured by free-flow micropuncture is equivocal, with studies that show either lower APR or similar APR in A1 -AR KO mice, compared to WT mice. Inhibition of A1 -ARs lowers elevated blood pressure in models of salt-sensitive hypertension, partially due to their effects in the proximal tubule. PMID:25345761

Welch, W J

2015-01-01

406

Na[superscript +] binding to meizothrombin desF1  

SciTech Connect

Meizothrombin is the physiologically active intermediate generated by a single cleavage of prothrombin at R320 to separate the A and B chains. Recent evidence has suggested that meizothrombin, like thrombin, is a Na{sup +}-activated enzyme. In this study we present the first X-ray crystal structure of human meizothrombin desF1 solved in the presence of the active site inhibitor PPACK at 2.1 {angstrom} resolution. The structure reveals a Na{sup +} binding site whose architecture is practically identical to that of human thrombin. Stopped-flow measurements of Na{sup +} binding to meizothrombin desF1 document a slow phase of fluorescence change with a k obs decreasing hyperbolically with increasing [Na{sup +}], consistent with the existence of three conformations in equilibrium, E*, E and E:Na{sup +}, as for human thrombin. Evidence that meizothrombin exists in multiple conformations provides valuable new information for studies of the mechanism of prothrombin activation.

Papaconstantinou, M.E.; Gandhi, P.S.; Chen, Z.; Bah, A.; Di Cera, E. (WU-MED)

2009-06-10

407

Adenosine, type 1 receptors: role in proximal tubule Na+ reabsorption  

PubMed Central

Adenosine type 1 receptor (A1-AR) antagonists induce diuresis and natriuresis in experimental animals and humans. Much of this effect is due to inhibition of A1-ARs in the proximal tubule, which is responsible for 60–70% of the reabsorption of filtered Na+ and fluid. Intratubular application of receptor antagonists indicates that A1-AR mediates a portion of Na+ uptake in PT and PT cells, via multiple transport systems, including Na+/H+ exchanger-3 (NHE3), Na+/PO4? co-transporter and Na+-dependent glucose transporter, SGLT. Renal microperfusion and recollection studies have shown that fluid reabsorption is reduced by A1-AR antagonists and is lower in A1-AR KO mice., compared to WT mice. Absolute proximal reabsorption (APR) measured by free-flow micropuncture is equivocal, with studies that show either lower APR or similar APR in A1-AR KO mice, compared to WT mice. Inhibition of A1-ARs lowers elevated blood pressure in models of salt-sensitive hypertension, partially due to their effects in the proximal tubule. PMID:25345761

Welch, William J

2015-01-01

408

Preparation and characterization of NaCS-CMC/PDMDAAC capsules.  

PubMed

A novel capsule system composed of sodium cellulose sulfate (NaCS), carboxymethyl cellulose (CMC) and poly[dimethyl(diallyl)ammonium chloride] (PDMDAAC) was prepared for improving the properties of NaCS/PDMDAAC capsules. The process parameters, such as CMC concentration (0, 2, 4, 6 and 8 g/L), NaCS concentration (20, 25, 30, 35 and 40 g/L), PDMDAAC concentration (20, 30, 40, 50, 60, 70 and 80 g/L), reaction time and temperature were investigated to understand their effects on the diameter, membrane thickness and mechanical strength of capsules. The optimum operation conditions for preparing NaCS-CMC/PDMDAAC capsules were determined as 6-8 g/L CMC, 35-40 g/L NaCS, 60 g/L PDMDAAC and polymerization for 30-40 min. Diffusion of substances with low molecular weight into capsules was investigated, and diffusion coefficients were calculated according to the developed model. The yeast of Candida krusei was chosen as representative cell to evaluate the effects of different cell loading on capsule mechanical strength. Meanwhile the encapsulated osmophilic C. krusei cells were cultured in 250 mL shaking flasks for 72 h to determine the cell leaking properties in short and long term. PMID:16199144

Chen, Guo; Yao, Shan-jing; Guan, Yi-xin; Lin, Dong-qiang

2005-11-10

409

[La Medicina del Lavoro: 100 volumes].  

PubMed

With these pages La Medicina del Lavoro starts its 100th volume, so we have yet another historical occasion to celebrate the oldest occupational health journal in the world that is still publishing. Over the last few years we have had many occasions to celebrate, for example several anniversaries of the Journal (the 80th volume in 1989, 90 years in 1992, 100 years in 2001); the centenary of the foundation of the Clinica del Lavoro "Luigi Devoto" of Milan in 2001; the celebration of the 300 years' anniversary of the publication of De Morbis Artificum Diatriba by Bernardino Ramazzini, and we obviously hope to continue for many years to come in this positive outlook. One hundred volumes makes for a very large collection, with the highs and lows ofthe Journal's history (here we mean the variations in number of pages and physical size of the Journal). It is thanks to the Editors-in-chief(there have been very few so we can cite them all: Luigi Devoto, 1901-1936; Luigi Preti, 1936-1941; Enrico Vigliani, 1943-1992; e Vito Foà, 1992 to the present); the contributors who in various ways and with varying degrees of commitment but always with an exceptional personal participation, that it has been possible to reach 100 volumes, starting with C. Moreschi who, along with Luigi Devoto, was the first and sole editor at the Journal's foundation; up to the present extended and impressive editorial board; the printers (from the first. Tipografia Cooperativa, Via dei Molini in Pavia, to the latest: Casa Editrice Mattioli in Fidenza); the sponsors, including the most evident who, via advertising (rather limited as a matter offact), directly gave information about themselves, but also those who have often been or are behind the scenes, ensuring fundamental support which is not visible; content. articles, news, events, reports, ideas, opinions, photographs, tables, numbers... etc, which are really impossible to sum up. But the true collection which, for obvious reasons, cannot be individually named, consists of the people and the ideas that have enriched the history of the Journal in its over 100 years of existence. And the subscribers, above all, who by their almost anonymous presence have been the true guarantors of the Journal's ife. And of course the contributors who with their articles have consigned a part of their lives to history. Starting from 1925 we counted nearly 11.000, a really grand number. It would be wonderful if we could invite them all to a hypothetical (and impossible) grand convention to simply say "Thank you, your contributions will not be forgotten". There have been 100 volumes but in actual fact the Journal is more than 100 years old. It was founded in Pavia in 1901 as Il Lavoro-Rivista di fisiologia, clinica ed igiene del lavoro, and between 1901 and 1910 only three volumes were published, then, due to the difficulties during the First World War and the immediate post-war years, there were no issues in 1916, 1918 and 1919. Issues finally became regular in 1920 with volume 11; from that moment on not one issue was missed and the Journal even got through the Second World War without interruptions. In 1925, with volume 16, it took on the name that still distinguishes it to-day: La Medicina del Lavoro, "the official standard bearer of a work of enormous scientific, social and political content" as Luigi Devoto presented the event at the time. The first few years of the Journal were difficult ones (with only three volumes published in 10 years) to the effect that events such as the First International Congress on Occupational Diseases (Milano, 1906), the foundation of the International Commission for Occupational Health (1906), the First National Italian Congress on Occupational Diseases (Palermo, 1907), and above all the inauguration of the Clinica del Lavoro in Milano (20 March, 1910) are not reported in the Journal, which by 1911 had resumed publication but had moved to Milan. Many years have passed since those first three volumes and in the meantime we have moved on to another century and

Zocchetti, C

2009-01-01

410

Multiatom covalent bonding and the formation enthalpy of Na2K  

NASA Astrophysics Data System (ADS)

We have made accurate pseudopotential calculations of the total energy of Na, K, and NaK in the CsCl structure, and Na2K in the MgZn2 structure. For Na2K, the only ordered alloy known to exist, we obtained a formation enthalpy, H=-16.1 meV/atom, whereas for NaK we obtained H=+7.5 meV/atom. We argue that the negative H of Na2K is a consequence of unusual covalent bonds involving more than two Na atoms.

Zhu, Ming J.; Bylander, D. M.; Kleinman, Leonard

1996-06-01

411

The Na(+) transporter, TaHKT1;5-D, limits shoot Na(+) accumulation in bread wheat.  

PubMed

Bread wheat (Triticum aestivum L.) has a major salt tolerance locus, Kna1, responsible for the maintenance of a high cytosolic K(+) /Na(+) ratio in the leaves of salt stressed plants. The Kna1 locus encompasses a large DNA fragment, the distal 14% of chromosome 4DL. Limited recombination has been observed at this locus making it difficult to map genetically and identify the causal gene. Here, we decipher the function of TaHKT1;5-D, a candidate gene underlying the Kna1 locus. Transport studies using the heterologous expression systems Saccharomyces cerevisiae and Xenopus laevis oocytes indicated that TaHKT1;5-D is a Na(+) -selective transporter. Transient expression in Arabidopsis thaliana mesophyll protoplasts and in situ polymerase chain reaction indicated that TaHKT1;5-D is localised on the plasma membrane in the wheat root stele. RNA interference-induced silencing decreased the expression of TaHKT1;5-D in transgenic bread wheat lines which led to an increase in the Na(+) concentration in the leaves. This indicates that TaHKT1;5-D retrieves Na(+) from the xylem vessels in the root and has an important role in restricting the transport of Na(+) from the root to the leaves in bread wheat. Thus, TaHKT1;5-D confers the essential salinity tolerance mechanism in bread wheat associated with the Kna1 locus via shoot Na(+) exclusion and is critical in maintaining a high K(+) /Na(+) ratio in the leaves. These findings show there is potential to increase the salinity tolerance of bread wheat by manipulation of HKT1;5 genes. PMID:25158883

Byrt, Caitlin Siobhan; Xu, Bo; Krishnan, Mahima; Lightfoot, Damien James; Athman, Asmini; Jacobs, Andrew Keith; Watson-Haigh, Nathan S; Plett, Darren; Munns, Rana; Tester, Mark; Gilliham, Matthew

2014-11-01

412

High-NA HPCS optical fibers for medical diagnosis and treatment  

NASA Astrophysics Data System (ADS)

Hard Plastic Clad Silica (HPCS) optical fibers with pure silica cores have been developed which are robust and have NA(Numerical Aperture)>0.50. Improved clad only HPCS fibers have been produced for both new 'standard' and 'high' NA versions. Based on new cladding formulations, the 'standard' NA fiber has an NA of 0.41, while the new ultrahigh NA fiber has an NA of 0.54. Mechanical strength and preliminary fatigue data are presented along with spectral characterization data. For the first time significant results were obtained for clad only high NA fibers, The fibers are useful for diagnostic and surgical applications. Short to medium length time to failure results, indicate that the static fatigue parameters of the new high numerical aperture (NA) optical fibers are at least as good as those for former standard NA (0.37) HPCS fibers, which is an advance from previous results on the older formulation high NA fibers.

Skutnik, Bolesh J.

2010-02-01

413

ACTUALIDAD INTERNACIONAL DEL TRATAMIENTO MAGNÉTICO PARA EL CONTROL DE INCRUSTACIONES. REVISIÓN  

Microsoft Academic Search

Luego de una breve descripción del proceso de endurecimiento del agua, se brinda una amplia información actualizada sobre la tecnología del tratamiento magnético del agua como método anti- incrustante en sistemas de intercambio de calor. Se destaca las principales hipótesis o mecanismos que pudieran responder a los efectos industriales observados, así como algunos de los resultados experimentales de los investigadores

Rigoberto del Toro Rodríguez; Arístides Berenguer Maurant

414

Doctor Harold Varmus, director del NCI: Bienvenidos a Cancer.gov en español  

Cancer.gov

El director del NCI, doctor Harold Varmus, da la bienvenida a los visitantes al sitio web del NCI y habla sobre la complejidad del cáncer, así como de los avances alcanzados gracias a las nuevas herramientas y tecnologías para la investigación del cáncer.

415

S. ArgentiniS. Argentini ISAC CNR Area di Ricerca di Roma Tor Vergata,Via del Fosso del Cavaliere, 100 00133 Roma,ISAC CNR Area di Ricerca di Roma Tor Vergata,Via del Fosso del Cavaliere, 100 00133 Roma,  

E-print Network

S. ArgentiniS. Argentini 11 ISAC ­ CNR Area di Ricerca di Roma Tor Vergata,Via del Fosso del Cavaliere, 100 00133 Roma,ISAC ­ CNR Area di Ricerca di Roma Tor Vergata,Via del Fosso del Cavaliere, 100 00133 Roma, Italy,Italy, s.argentini@isac.cnr.its.argentini@isac.cnr.it SUMMARYSUMMARY The siteThe site

Ribes, Aurélien

416

Inelastic cold collisions of a Na/Rb mixture in a magneto-optical trap  

NASA Astrophysics Data System (ADS)

We report results on inelastic cold collisions for a mixed species magneto-optical trap containing Na and Rb. The rate of collisional trap loss of Na is due to different contributions: Na-Na and Na-Rb collisions. Both parts are investigated with respect to trap laser intensity and frequency. The observations are explained based on a Gallagher-Pritchard model. Possibilities for studies and applications involving mixed species traps are discussed.

Telles, G. D.; Marcassa, L. G.; Muniz, S. R.; Miranda, S. G.; Antunes, A.; Westbrook, C.; Bagnato, V. S.

1999-01-01

417

Multibubble sonoluminescence pulses from Na atoms in viscous liquid.  

PubMed

Multibubble sonoluminescence pulses of Na and continuum emissions were measured from NaCl-ethylene glycol solution saturated with Xe at 28 kHz. The Na emission consisted of multiple-peak pulses and single pulses. The intrinsic pulse width estimated from single pulses was 0.37 ns, which differs from 10-165 ns obtained by previous work. High-speed shadowgraphs of bubble dynamics and high-speed movies (32000 fps) of sonoluminescence were observed. The observations suggest that the multiple-peak pulse is due to the superposition of single peaks resulting from bubbles fragmented from a characteristic bubble which repeats the fragmentation and coalescence. This phenomenon may be specific to viscous liquids. PMID:22559461

Choi, Pak-Kon; Sawada, Yosuke; Takeuchi, Yuuta

2012-05-01

418

Superconducting properties and electronic structure of NaBi.  

PubMed

Resistivity, dc magnetization, and heat capacity measurements are reported for superconducting NaBi. T(c), the electronic contribution to the specific heat ?, the ?C(p)/?T(c) ratio, and the Debye temperature are found to be 2.15?K, 3.4?mJ?mol(-1)?K(-2), 0.78, and 140?K respectively. The calculated electron-phonon coupling constant (?(ep) = 0.62) implies that NaBi is a moderately coupled superconductor. The upper critical field and coherence length are found to be 250?Oe and 115?nm, respectively. Electronic structure calculations show NaBi to be a good metal, in agreement with the experiments; the p(x) and p(y) orbitals of Bi dominate the electronic states at the Fermi Energy. PMID:24804822

Kushwaha, S K; Krizan, J W; Xiong, J; Klimczuk, T; Gibson, Q D; Liang, T; Ong, N P; Cava, R J

2014-05-28

419

Investigation of the 19Na via resonance elastic scattering  

E-print Network

The structure of the unbound proton-rich isotope 19Na was studied in resonance elastic scattering of a radioactive 18Ne beam on a proton target using the thick-target inverse-kinematics method. The experiment covered excitation energy range from 0.5 to 2.7 MeV in c.m.s. Only one state of 19Na (the second excited state) was observed. A combined R-matrix and potential-model analysis was performed. The spin and parity assignment of this second excited state was confirmed to be 1/2+. We showthat the position of the 1/2+ state significantly affects the reaction rate through that state but the total reaction rate remains unchanged since the 18Ne(2p,gamma) proceeds mostly via the ground and first excited states in 19Na at stellar temperatures.

B. B. Skorodumov; G. V. Rogachev; P. Boutachkov; A. Aprahamian; J. J. Kolata; L. O. Lamm; M. Quinn; A. Woehr

2006-09-26

420

Investigation of the 19Na via resonance elastic scattering  

E-print Network

The structure of the unbound proton-rich isotope 19Na was studied in resonance elastic scattering of a radioactive 18Ne beam on a proton target using the thick-target inverse-kinematics method. The experiment covered excitation energy range from 0.5 to 2.7 MeV in c.m.s. Only one state of 19Na (the second excited state) was observed. A combined R-matrix and potential-model analysis was performed. The spin and parity assignment of this second excited state was confirmed to be 1/2+. We showthat the position of the 1/2+ state significantly affects the reaction rate through that state but the total reaction rate remains unchanged since the 18Ne(2p,gamma) proceeds mostly via the ground and first excited states in 19Na at stellar temperatures.

Skorodumov, B B; Boutachkov, P; Kolata, J J; Lamm, L O; Quinn, M; Rogachev, G V; Wöhr, A

2006-01-01

421

Binding energy and structure of e+Na  

NASA Astrophysics Data System (ADS)

We calculate the nonadiabatic binding energy and geometry of the weakly bound state of e+Na. We use the Peach model potential, which includes both the dipole and an effective quadrupole term in the polarization, to describe the interaction of the electron and positron with the ion core. The effective three-body Schrödinger equation is solved with the finite element method. Because the model potential gives rise to three spurious states, the true ground state of e+Na is embedded in a dense spectrum of spurious states. We develop a method for extracting the correct ground state for e+Na, even when the energy is nearly degenerate with a spurious level. The calculated value for the binding energy is consistent with other calculations.

Shertzer, J.; Ward, S. J.

2010-06-01

422

The stability of sodalite in the system NaAlSiO sub 4 -NaCl  

SciTech Connect

The reaction sodalite = {beta}-nepheline + NaCl (s) was reversed in solid-medium apparatus and the reaction sodalite = carnegieite + NaCl (l) was reversed at 1 bar (1,649-1,652 K). The experimental reversals between 923 K and 973 K can be fit with a dP/dT of {minus}11 bar/K, suggesting that the excess entropy for sodalite is present only above 923 K. A phase diagram for the NaAlSiO{sub 4}-NaCl system that is consistent with the measured thermochemical data and the experiments between 973 and 1,650 K can be generated if the 61.7 J/mol{center dot}K entropy contribution is included in the S{sup 0}{sub 298} of sodalite. This entropy contribution must be removed below 973 K for the experiments to fit with calculations. Previously unreported thermodynamic data estimated in this study are {Delta}G{sup 0}{sub 298} for sodalite ({minus}12,697 kJ/mol) and carnegieite (NaAlSiO{sub 4}) ({minus}1,958 kJ/mol), S{sup 0}{sub 298} of carnegieite (129.6 J/mol{center dot}K) and compressibility of NaCl{sub liquid} (V{sup P}{sub 298} (cm{sup 3}) = 31.6{center dot}(1 - 24.7{center dot}10{sup {minus}3}{center dot}P + 800{center dot}10{sup {minus}6}{center dot}P{sup 2}))(T in K; P in kbar). Sodalite is a high-temperature, low-pressure phase, stable well above the solidus in sodic silica-undersaturated magmas enriched in NaCl, and its presence constrains NaCl activities in magmas. Estimates of minimum NaCl (l) activities in the Mont St-Hilaire sodalite syenites are 0.05 at 1,073 K and 0.13 at 1,273 K. Density calculations are consistent with the field observations that sodalite phenocrysts will float in a nepheline syenite liquid. This explains the enrichment of sodalite in the upper levels of the sodalite syenites at Mont St.Hilaire and elsewhere.

Sharp, Z.D. (Carnegie Institution of Washington, DC (USA)); Helffrich, G.R. (Northwestern Univ., Evanston, IL (USA)); Bohlen, S.R. (S.U.N.Y., Stony Brook, NY (USA)); Essene, E.J. (Univ. of Michigan, Ann Arbor (USA))

1989-08-01

423

Plant response to Na/sup +/, K/sup +/ and K/sup +//Na/sup +/ ratios under saline conditions  

SciTech Connect

This research was undertaken to more clearly determine plant response to saline-sodic waters. In the first experiment, the response of wheat and sorghum to different K/sup +//Na/sup +/ ratios at different osmotic potentials was investigated. The plants were grown in outdoor solution culture tanks containing polyethylene glycol and/or NaCl as osmoticum with 1/2 strength Hoagland as the base nutrient solution. The mass of the root system for both wheat and sorghum was determined primarily by the osmotic potential. However, root elongation was controlled primarily by the Na/sup +/ concentration. Sorghum root elongation rates decreased with increasing Na/sup +/ while those for wheat increased. Sodium was not translocated out of the sorghum root system until a critical Na/sup +/ root saturation level of .6 moles/kg was obtained. The second experiment was designed to investigate the water, nutrient and growth responses of the second crop of wheat in a wheat-sorghum-wheat rotation to zonal saline-sodic conditions.

Devitt, D.A.

1983-01-01

424

Measurement of the low-energy Na+-Na total collision rate in an ion-neutral hybrid trap  

NASA Astrophysics Data System (ADS)

We present measurements of the total elastic and resonant charge-exchange ion-atom collision rate coefficient kia of cold sodium (Na) with optically dark low-energy Na+ ions in a hybrid ion-neutral trap. To determine kia, we measured the trap loading and loss rates from both a Na magneto-optical trap (MOT) and a linear radio-frequency quadrupole Paul trap. We found the total rate coefficient to be 7.4 ±1.9 ×10-8 cm3/s for the type-I Na MOT immersed within an ?140 -K ion cloud and 1.10 ±0.25 ×10-7 cm3/s for the type-II Na MOT within an ?1070 -K ion cloud. Our measurements show excellent agreement with previously reported theoretical fully quantal ab initio calculations. In the process of determining the total rate coefficient, we demonstrate that a MOT can be used to probe an optically dark ion cloud's spatial distribution within a hybrid trap.

Goodman, D. S.; Wells, J. E.; Kwolek, J. M.; Blümel, R.; Narducci, F. A.; Smith, W. W.

2015-01-01

425

Performance of lime-BHA solidified plating sludge in the presence of Na2SiO3 and Na2CO3.  

PubMed

This research investigated the performance of lime-BHA (black rice husk ash) solidified plating sludge with 2 wt% NaO from Na(2)SiO(3) and Na(2)CO(3) at the level of 0, 30 and 50 wt%. The sludge was evaluated for strength development, leachability, solution chemistry and microstructure. The lime-BHA solidified plating sludge with Na(2)SiO(3) and Na(2)CO(3) had higher early strength when compared to the control. The addition of Na(2)SiO(3) and Na(2)CO(3) increased the OH(-) concentration and decreased the Ca(2+) and heavy metal ions in solution after the first minute. The XRD patterns showed that the addition of Na(2)SiO(3) resulted in the formation of calcium silicate hydrates, while the addition of Na(2)CO(3) resulted in CaCO(3). The heavy metals from the plating sludge, especially Zn, were immobilized in calcium zincate and calcium zinc silicate forms for the lime-BHA with and without Na(2)SiO(3) solidified wastes, while samples with Na(2)CO(3) contained Zn that was fixed in the form of CaZnCO(3). The cumulative leaching of Fe, Cr and Zn from the lime-BHA solidified plating sludge decreased significantly when activators were added, especially Na(2)CO(3). PMID:21549500

Piyapanuwat, Rungroj; Asavapisit, Suwimol

2011-09-01

426

Pancreatic ?-cell Na+ channels control global Ca2+ signaling and oxidative metabolism by inducing Na+ and Ca2+ responses that are propagated into mitochondria.  

PubMed

Communication between the plasma membrane and mitochondria is essential for initiating the Ca(2+) and metabolic signals required for secretion in ? cells. Although voltage-dependent Na(+) channels are abundantly expressed in ? cells and activated by glucose, their role in communicating with mitochondria is unresolved. Here, we combined fluorescent Na(+), Ca(2+), and ATP imaging, electrophysiological analysis with tetrodotoxin (TTX)-dependent block of the Na(+) channel, and molecular manipulation of mitochondrial Ca(2+) transporters to study the communication between Na(+) channels and mitochondria. We show that TTX inhibits glucose-dependent depolarization and blocks cytosolic Na(+) and Ca(2+) responses and their propagation into mitochondria. TTX-sensitive mitochondrial Ca(2+) influx was largely blocked by knockdown of the mitochondrial Ca(2+) uniporter (MCU) expression. Knockdown of the mitochondrial Na(+)/Ca(2+) exchanger (NCLX) and Na(+) dose response analysis demonstrated that NCLX mediates the mitochondrial Na(+) influx and is tuned to sense the TTX-sensitive cytosolic Na(+) responses. Finally, TTX blocked glucose-dependent mitochondrial Ca(2+) rise, mitochondrial metabolic activity, and ATP production. Our results show that communication of the Na(+) channels with mitochondria shape both global Ca(2+) and metabolism signals linked to insulin secretion in ? cells.- Nita, I. I., Hershfinkel, M., Kantor, C., Rutter, G. A., Lewis, E. C., Sekler, I. Pancreatic ?-cell Na(+) channels control global Ca(2+) signaling and oxidative metabolism by inducing Na(+) and Ca(2+) responses that are propagated into mitochondria. PMID:24719357

Nita, Iulia I; Hershfinkel, Michal; Kantor, Chase; Rutter, Guy A; Lewis, Eli C; Sekler, Israel

2014-08-01

427

UNIVERSIDAD NACIONAL AUTNOMA DE MXICO Datos del plan de estudio  

E-print Network

Futbol asociación Dirigido a: Entrenadores de la DGADyR, Comunidad Universitaria y Público General la técnica en el futbol para el grado ii III.- Técnica del portero aplicada al juego de conjunto a la

Islas, León

428

MEMORIA 2011 Torre de Control del antiguo aerdromo de Alicante  

E-print Network

MEMORIA 2011 Torre de Control del antiguo aeródromo de Alicante Nueva entrada a la UA enlace TRAM .........................................................................................................5 2.1 Resultados gestión de la calidad

Escolano, Francisco

429

Paso del Norte Watershed Council Coordinated Water Resources Database Project  

E-print Network

The Paso del Norte Watershed Council (PDNWC) is a quasi-governmental organization that serves in an advisory capacity to the New Mexico-Texas Water Commission regarding the selection, planning, and implementation of environmental enhancements...

Brown, Christopher; Sheng, Zhuping; Rich, Matt

430

La Revolucin del Shale Gas Profesor: Hugh Rudnick  

E-print Network

La Revolución del Shale Gas Mayo 2011 Profesor: Hugh Rudnick Profesional Externo: Verónica Cortés........................................................................................................................................ 6 ¿Qué es el Shale Gas...................................................................................................................................... 7 Shale Gas

Rudnick, Hugh

431

Trasmissione numerica: Compito del 10/02/2011 Esercizio 1  

E-print Network

' AWGN con densita' spettrale di potenza media bilatera N0/2, i segnali hanno uguale prob- abilita' un rumore AWGN con densita' spettrale di potenza media bilatera N0/2. L'energia del segnale trasmesso

Abrardo, Andrea

432

77 FR 47360 - Del Norte Resource Advisory Committee  

Federal Register 2010, 2011, 2012, 2013, 2014

...authorized under the Secure Rural Schools and Community Self-Determination...the Del Norte County Unified School District, Redwood Room...Six Rivers National Forest Supervisor's Office, 1330 Bayshore...Six Rivers National Forest Supervisor's Office, 1330...

2012-08-08

433

DEPARTAMENTO DE INGENIERIA INFORMATICA Normativas para el Programa Doctorado del  

E-print Network

DEPARTAMENTO DE INGENIERIA INFORMATICA Normativas para el Programa Doctorado del Departamento de Valiente, 11. Madrid, 28049. Teléfono: 914972230 #12;DEPARTAMENTO DE INGENIERIA INFORMATICA 4. Una vez

Autonoma de Madrid, Universidad

434

FRAGOMEN, DEL REY, BERNSEN & LOEWY, LLP US IMMIGRATION CLIENT ALERT  

E-print Network

FRAGOMEN, DEL REY, BERNSEN & LOEWY, LLP US IMMIGRATION CLIENT ALERT If you have any questions about to the United States. This Client Alert provides general guidance on procedures, including visa issuance at U

Scharer, John E.

435

Sapienza Universit di Roma Direttore del Dipartimento: Prof. Fabio Grasso  

E-print Network

posseduti dai candidati alla data della scadenza del termine utile per la presentazione delle domande di quale inviare ogni comunicazione, ivi comprese le convocazioni per il colloquio, senza che vi sia altro

Guidoni, Leonardo

436

Facultad de Estudios Superiores Acatln Datos del plan de estudio  

E-print Network

Dirigido a: Profesionales que deseen desarrollarse en las áreas de comercio internacional, gestión aduanera y negocios internacionales. Empresarios relacionados al comercio internacional. Personas interesadasFacultad de Estudios Superiores Acatlán Datos del plan de estudio Diplomado: Comercio exterior

Islas, León

437

Modular cell biology: retroactivity and insulation Domitilla Del Vecchio1,  

E-print Network

Modular cell biology: retroactivity and insulation Domitilla Del Vecchio1, *, Alexander J Ninfa2 a remarkable insulation property, due to the fast timescales of the phosphorylation and dephosphorylation: computational methods; metabolic and regulatory networks Keywords: feedback; insulation; modularity; singular

Sontag, Eduardo

438

Ability of multicellular salt glands in Tamarix species to secrete Na+ and K+ selectively.  

PubMed

The present study aimed to determine the mechanism of cation-selective secretion by multicellular salt glands. Using a hydroponic culture system, the secretion and accumulation of Na(+) and K(+) in Tamarix ramosissima and T. laxa under different salt stresses (NaCl, KCl and NaCl+KCl) were studied. Additionally, the effects of salt gland inhibitors (orthovanadate, Ba(2+), ouabain, tetraethylammonium (TEA) and verapamil) on Na(+) and K(+) secretion and accumulation were examined. Treatment with NaCl (at 0-200 mmol L(-1) levels) significantly increased Na(+) secretion, whereas KCl treatment (at 0-200 mmol L(-1) levels) significantly increased K(+) secretion. The ratio of secretion to accumulation of Na(+) was higher than that of K(+). The changes in Na(+) and K(+) secretion differed after adding different ions into the single-salt solutions. Addition of NaCl to the KCl solution (at 100 mmol L(-1) level, respectively) led to a significant decrease in K(+) secretion rate, whereas addition of KCl to the NaCl solution (at 100 mmol L(-1) level, respectively) had little impact on the Na(+) secretion rate. These results indicated that Na+ secretion in Tamarix was highly selective. In addition, Na(+) secretion was significantly inhibited by orthovanadate, ouabain, TEA and verapamil, and K(+) secretion was significantly inhibited by ouabain, TEA and verapamil. The different impacts of orthovanadate on Na(+) and K(+) secretion might be the primary cause for the different Na(+) and K(+) secretion abilities of multicellular salt glands in Tamarix. PMID:21416329

Ma, Haiyan; Tian, Changyan; Feng, Gu; Yuan, Junfeng

2011-03-01

439

Difusión de resultados iniciales del Estudio del Tamoxifeno y del Raloxifeno (STAR): el fármaco para el tratamiento de la osteoporosis, raloxifeno, es tan efectivo como el Tamoxifeno en la prevención de cáncer de seno invasor  

Cancer.gov

Los resultados iniciales del Estudio del Tamoxifeno y del Raloxifeno, STAR, demuestran que el fármaco raloxifeno, actualmente utilizado para prevenir y tratar la osteoporosis en mujeres posmenopáusicas, funciona tan bien como el tamoxifeno para reducir el riesgo de cáncer de seno entre las mujeres posmenopáusicas que tienen riesgo elevado de padecer la enfermedad. Preguntas y respuestas

440

Brain Na+, K+-ATPase Activity In Aging and Disease  

PubMed Central

Na+/K+ pump or sodium- and potassium-activated adenosine 5’-triphosphatase (Na+, K+-ATPase), its enzymatic version, is a crucial protein responsible for the electrochemical gradient across the cell membranes. It is an ion transporter, which in addition to exchange cations, is the ligand for cardenolides. This enzyme regulates the entry of K+ with the exit of Na+ from cells, being the responsible for Na+/K+ equilibrium maintenance through neuronal membranes. This transport system couples the hydrolysis of one molecule of ATP to exchange three sodium ions for two potassium ions, thus maintaining the normal gradient of these cations in animal cells. Oxidative metabolism is very active in brain, where large amounts of chemical energy as ATP molecules are consumed, mostly required for the maintenance of the ionic gradients that underlie resting and action potentials which are involved in nerve impulse propagation, neurotransmitter release and cation homeostasis. Protein phosphorylation is a key process in biological regulation. At nervous system level, protein phosphorylation is the major molecular mechanism through which the function of neural proteins is modulted in response to extracellular signals, including the response to neurotransmitter stimuli. It is the major mechanism of neural plasticity, including memory processing. The phosphorylation of Na+, K+-ATPase catalytic subunit inhibits enzyme activity whereas the inhibition of protein kinase C restores the enzyme activity. The dephosphorylation of neuronal Na+, K+-ATPase is mediated by calcineurin, a serine / threonine phosphatase. The latter enzyme is involved in a wide range of cellular responses to Ca2+ mobilizing signals, in the regulation of neuronal excitability by controlling the activity of ion channels, in the release of neurotransmitters and hormones, as well as in synaptic plasticity and gene transcription. In the present article evidence showing Na+, K+-ATPase involvement in signaling pathways, enzyme changes in diverse neurological diseases as well as during aging, have been summarized. Issues refer mainly to Na+, K+-ATPase studies in ischemia, brain injury, depression and mood disorders, mania, stress, Alzheimer´s disease, learning and memory, and neuronal hyperexcitability and epilepsy. PMID:25018677

de Lores Arnaiz, Georgina Rodríguez; Ordieres, María Graciela López

2014-01-01

441

Branching ratios for the beta decay of Na-21  

E-print Network

relationship: R1 = N?? N?#4;? k, (1) where N?? is the number of 351-keV ? rays observed in coincidence with betas; N? is the number of (singles) betas observed; #4;? is the efficiency of the HPGe detector for 351-keV ? rays; and k is a factor (?1... ? rays ob- served in coincidence with positrons following the decay of 21Na. It includes about half of the total data collected. The peaks attributable to 21Na are marked with their energy in keV; the sum peak is identified by its components...

Iacob, V. E.; Hardy, John C.; Gagliardi, Carl A.; Goodwin, J.; Nica, N.; Park, H. I.; Tabacaru, G.; Trache, L.; Tribble, Robert E.; Zhai, Y.; Towner, I. S.

2006-01-01

442

Efficiency of the Modular Neutron Array (MoNA)  

SciTech Connect

The efficiency of the Modular Neutron Array (MoNA), located at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University, was measured and compared to simulations. The Coulomb dissociation of a 90 MeV/u beam of {sup 11}Be in a gold target was used to produce neutrons. The expected neutron production rate was calculated using the virtual photon method. The measured efficiency agrees with the efficiency calculated with GEANT simulations. The current configuration of MoNA has a 73% intrinsic detection efficiency for 90 MeV neutrons.

Peters, W. A. [Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854 (United States); National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, ML 48824 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, ML 48824 (United States); Baumann, T. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, ML 48824 (United States); Christian, G. A.; Strongman, M. J. [Department of Physics and Astronomy, Michigan State University, East Lansing, ML 48824 (United States); Denby, D.; DeYoung, P. A.; Hall, C. C. [Department of Physics, Hope College, Holland, ML 49423 (Netherlands); Finck, J. E. [Department of Physics, Central Michigan University, Mt. Pleasant, MI 48859 (United States); Frank, N. [Physics Department, Illinois Wesleyan University, Bloomington, LL 61701 (United States); Hinnefeld, J. [Department of Physics, Indiana University South Bend, South Bend, LN 46634 (United States); Schiller, A. [Department of Physics and Astronomy, Ohio University, Athens, OH 45701 (United States); Thoennessen, M. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, ML 48824 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, ML 48824 (United States)

2009-03-10

443

The NA62 Liquid Krypton Electromagnetic Calorimeter Level 0 Trigger  

E-print Network

The NA62 experiment at CERN SPS aims to measure the Branching Ratio of the very rare kaon decay K+ -> pi+ nu nubar collecting O(100) events with a 10% background to make a stringent test of the Standard Model. One of the main backgrounds to the proposed measurement is represented by the K+ -> pi+ pi0 decay. To suppress this background an efficient photo veto system is foreseen. In the 1-10 mrad angular region the NA48 high performance liquid krypton electromagnetic calorimeter is used. The design, implementation and current status of the Liquid Krypton Electromagnetic Calorimeter Level 0 Trigger are presented.

Bonaiuto, V; Paoluzzi, G; Salamon, A; Salina, G; Santovetti, E; Sargeni, F; Scarfì, F M

2012-01-01

444

The NA62 Liquid Krypton Electromagnetic Calorimeter Level 0 Trigger  

E-print Network

The NA62 experiment at CERN SPS aims to measure the Branching Ratio of the very rare kaon decay K+ -> pi+ nu nubar collecting O(100) events with a 10% background to make a stringent test of the Standard Model. One of the main backgrounds to the proposed measurement is represented by the K+ -> pi+ pi0 decay. To suppress this background an efficient photo veto system is foreseen. In the 1-10 mrad angular region the NA48 high performance liquid krypton electromagnetic calorimeter is used. The design, implementation and current status of the Liquid Krypton Electromagnetic Calorimeter Level 0 Trigger are presented.

V. Bonaiuto; A. Fucci; G. Paoluzzi; A. Salamon; G. Salina; E. Santovetti; F. Sargeni; F. M. Scarfi'

2012-01-16

445

The NA62 Liquid Krypton Electromagnetic Calorimeter Level 0 Trigger  

E-print Network

The NA62 experiment at CERN SPS aims to measure the Branching Ratio of the very rare kaon decay K+ -> pi+ nu nubar collecting O(100) events with a 10% background to make a stringent test of the Standard Model. One of the main backgrounds to the proposed measurement is represented by the K+ -> pi+ pi0 decay. To suppress this background an efficient photo veto system is foreseen. In the 1-10 mrad angular region the NA48 high performance liquid krypton electromagnetic calorimeter is used. The design, implementation and current status of the Liquid Krypton Electromagnetic Calorimeter Level 0 Trigger are presented.

Vincenzo Bonaiuto; Adolfo Fucci; Giovanni Paoluzzi; Andrea Salamon; Gaetano Salina; Emanuele Santovetti; Fausto Sargeni; Francesco M. Scarfi'

2012-01-18

446

Possible selective adsorption of enantiomers by Na-montmorillonite  

NASA Technical Reports Server (NTRS)

Racemic amino acids including (D,L) alpha-alamine, (D,L) alpha-aminobutyric acid, (D,L) valine, and (D,L) norvaline were incubated with Na-montmorillonite at 100% CEC at three hydrogen ion concentrations, and amino acid adsorption was determined by ion exchange chromatography. Enantiomers were analyzed by gas chromatography. Differences in the quantities of D and L enantiomers in any of the fractions was no larger than a few percent. Although a large difference in the adsorption of the amino acid enantiomers was not observed, the analysis may indicate a small preferential adsorption (0.5-2%) of L-amino acids by Na-montmorillonite.

Friebele, E.; Shimoyama, A.; Ponnamperuma, C.

1981-01-01

447

MAKSIMALNA UBRZANJA NA SPRATOVIMA VIŠESPRATNIH ZGRADA Rezime  

Microsoft Academic Search

Za obezbe)enje sigurnost krutih nenose*ih komponenti u konstrukcijama zgrada važno je ta(no i jednostavno odrediti najve*a ubrzanja na spratovina gde se ove komponente nalaze, za odredjen seizmi(ki hazard. Nedavno predloženo pravilo, na bazi superpozicije karakteristi(nih funkcija konstrukcije, je dalje usavršeno (ime se postiže ta(nija ocena u slu(ajevima kad silno pomeranje sadrži duge periode. Numeri(ke analize pokazuju da predloženo pravilo daje

Vinay K. Gupta; Manish Kumar; Dharmendra Kumar

448

Clean demarcation of cartilage tissue 23Na by inversion recovery.  

PubMed

Monitoring the sodium concentration in vivo using 23Na MRI can be an important tool for assessing the onset of tissue disorders. Practical clinical 23Na MRI methods furthermore often do not allow one to use sufficiently small voxel sizes such that only the tissue of interest is seen, but a large signal contamination can arise from sodium in synovial fluid. Here we demonstrate that applying an inversion recovery (IR) technique allows one to distinctly select either the cartilage-bound or the free sodium for visualization in an image. The results are validated both ex vivo and in vivo. PMID:18502158

Rong, Peng; Regatte, Ravinder R; Jerschow, Alexej

2008-08-01

449

Russian Scientific-Educational Project: Kazan-GeoNa-2017  

NASA Astrophysics Data System (ADS)

For the further successful development of educational and scientific - educational activity of the Russian Federation, the Republic Tatarstan, Kazan is offered the national project - the International Center of the Science and the Internet of Technologies. "GeoNa" (Geometry of Nature - "GeoNa" is developed - wisdom, enthusiasm, pride, grandeur), which includes a modern complex of conference halls (up to 4 thousand places), the Center the Internet of Technologies, 3D Planetarium - development of the Moon, PhysicsLand, an active museum of natural sciences, an oceanarium, training a complex «Spheres of Knowledge», botanical and landscape oases.

Gusev, A.; Alibekova, N.

2012-09-01

450

Na+ and Li+ NASICON Superionic Conductors Thick Films  

Microsoft Academic Search

For microionic applications, superionic conductors have been elaborated in the form of thick films, using silk-screen printable powders. Na3Zr2Si2PO12, Na3.1Zr1.55Si2.3P0.7O11 and Li0.8Zr1.8Ta0.2(PO4)3 compositions are synthesized by a sol-gel process involving hydrolysis-polycondensation reactions of metal-organic alcoholic solutions. A thermal treatment (600°C-800°C) allows to obtain very fine particles (<1 mum) with the pure NASICON phase. Inks are prepared with these powders, an

H. Perthuis; G. Velasco; Ph. Colomban

1984-01-01

451

Crystallization patterns of membrane-bound (Na+ +K+)-ATPase.  

PubMed

Extensive formation of two-dimensional crystals of the proteins of the pure membrane-bound (Na+ +K+)-ATPase is induced during prolonged incubation with vanadate and magnesium. Some membrane crystals are formed in medium containing magnesium and phosphate. Computer-averaged images of the two-dimensional crystals show that the unit cell in vanadate-induced crystals contains a protomeric alpha beta-unit of the enzyme protein. In phosphate-induced crystals an (alpha beta) 2-unit occupies one unit cell suggesting the interactions between alpha beta-units can be of importance in the function of the Na+, K+ pump. PMID:6289891

Hebert, H; Jørgensen, P L; Skriver, E; Maunsbach, A B

1982-08-12

452

L’eruzione laterale etnea del novembre 1950 — dicembre 1951  

Microsoft Academic Search

Conclusione  L’eruzione etnea del 1950–51 si manifestata quasi senza segni premonitori, dopo una breve (meno di un anno) stasi del vulcano.\\u000a Essa si stabilita in una zona che stata gi teatro di precedenti eruzioni (1811) ed ha avuto un’attivit prevalentemente\\u000a effusiva di notevole durata. La lava emessa ha la composizione mineralogica identica alle lave emesse in questo secolo; essa\\u000a si differenzia

Gustavo Cumin

1954-01-01

453

Mecanica del Solido Deformable Presentacion de la asignatura  

E-print Network

Mec´anica del S´olido Deformable Presentaci´on de la asignatura Profesor Ignacio Romero E consulta (en la biblioteca): -- Introducci´on a la mec´anica de los s´olidos. Zubizarreta, V. y Ros, A asignatura 6 · La Mec´anica de S´olidos trata del estudio de modelos de comportamiento de s

Romero, Ignacio

454

La construccin del discurso en el siglo XIII  

E-print Network

« literarios », y, por otro, de las « creencias », más que « ideas », acerca de cómo evoluciona la sintaxis en « supraoracional », y cae bajo el análisis del discurso, más que de la sintaxis tradicional). 1.1. Las creencias suma, no usa la subordinación sintáctica, porque le bastan otros medios3, creencia nacida además del

Paris-Sud XI, Université de

455

Pedro, Juan y Diego: Obra fundacional del teatro contestario chileno  

E-print Network

paradigma en la adquisición de bienes de consumo y su sueño máximo era el vehículo propio. Para materializar este sueño los individuos debían ingresar al sistema de relaciones típicas del mundo impersonal del dinero, priorizando la competitividad y... Austin Mini-Toyota-Frigidaire... ¡Super compacta! ¡Una verdadera proeza de la tecnología nipona!" (102). Diego tenía una sociedad con otros ex-compañeros, todos desempleados ahora, que alimentaban este sueño que veía ya como imposible. El vehículo iba...

Lepeley, Oscar

2001-04-01

456

Aspectos clínicos de la biología molecular del cáncer de próstata  

Microsoft Academic Search

Resumen  La tecnología del ADN recombinante ha sido una herramienta invaluable para entender los mecanismos de carcinogénesis. Por\\u000a ejemplo, hemos podido conocer que en nuestro propio genoma existen genes con la capacidad de inducir transformación maligna\\u000a (oncogenes) on con la capacidad de bloquearla (genes supresores de tumores). Esta tecnología también nos ha permitido desarrollar\\u000a nuevas estrategias de diagnóstico y tratamiento del

Diana González-Espinosa; Miguel A. Jiménez Ríos; Andrés A. Gutiérrez-López

2002-01-01

457

La generación de 1924: El dilema del realismo  

E-print Network

, Celestino Gorostiza, repite sólo en parte esta trayectoria que estamos esbozando. Sus primeras obras reflejan intereses intelectuales típicos del momento. El nuevo paraíso (1930) recuerda los Autos de Villaurrutia en su visión de un Edén abstracto en el... dentro de las convenciones de su tipo: mucho movimiento, exageración, bailarinas en mallas, chanzas al arte abstracto, y moraleja final. La sátira halla sus blancos en diversos sectores de la vida publica y privada, tales como la corrupción del...

Dauster, Frank

1985-04-01

458

Del carnaval como 'metáfora' al teatro de carnaval  

E-print Network

la década de 1980) persigue contribuir al desarrollo de una manera más productiva de visualizar el teatro del carnaval, y en general, la práctica teatral en la actualidad. Actuación de la Anti-Murga BCG en el tablado "El Monumental del Control... funcionalizadas año tras año con ese fin. El escenario, el panel de fondo (comercial o alegórico), los asientos, la boletería, las paredes circundantes, se construyen de chapas, bloques y tablones. Cables y lamparitas colgantes, letreros, pintadas y graffitis...

Remedi, Gustavo

2001-04-01

459

Aportació a coneixement florístic del Moianès (Catalunya central)  

Microsoft Academic Search

Seguint en la línia d'ampliació del coneixement florístic de l'àrea del Moianès, presentem dades d'interès corològic de 46 tàxons. Es tracta bàsicament d'espècies d'ambients forestals i pradencs, bona part no citades d'aquest sector i algunes de molt rares o inexistents al territori ausosegàrric. Hi ha un primer grup d'espècies, que a les terres catalanes són bàsicament pirinenques [Linum viscosum L.,

Arnau Mercadé López

2007-01-01

460

Glucocorticoid stimulation of ileal Na+ absorptive cell brush border Na+/H+ exchange and association with an increase in message for NHE-3, an epithelial Na+/H+ exchanger isoform.  

PubMed

Methylprednisolone stimulates rabbit ileal neutral NaCl absorption; and aminoglutethimide, which decreases glucocorticoid levels, decreases NaCl absorption. Studies were carried out to determine the mechanism of these effects and to determine which members of the gene family of mammalian Na+/H+ exchangers were involved. Rabbits were treated subcutaneously with methylprednisolone (40 mg daily for 24 or 72 h), aminoglutethimide (100 mg twice daily for 72 h), or saline as a control. Ileal brush border membranes were prepared by magnesium precipitation, and brush border Na+/H+ exchange was determined by 22Na+ uptake over 3-8 s. The 22Na+ uptake experiments were performed in the presence of a voltage clamp using either valinomycin/potassium or tetramethylammonium/nitrate to eliminate potential contributions by other electrogenic transport processes. Methylprednisolone treatment approximately doubled ileal brush border Na+/H+ exchange, whereas aminoglutethimide led to a 50% decrease in Na+/H+ exchange. These effects were specifically on Na+ uptake with an acid inside pH gradient, whereas diffusive Na+ uptake (no pH gradient), glucose-dependent Na+ uptake, and glucose and Na+ equilibrium volumes were not affected. To determine if the increase in Na+/H+ exchange was associated with an increase in message expression, mRNA levels were measured by ribonuclease protection assay. Methylprednisolone stimulated the NHE-3 mRNA level by 4-6-fold at 24 h, which remained increased at 72 h. In contrast, messages for NHE-1 and NHE-2 were not affected by methylprednisolone. In summary, 1) methylprednisolone stimulation of rabbit ileal Na+ absorption is due to stimulation of ileal villus cell brush border Na+/H+ exchange; 2) basal ileal brush border Na+/H+ exchange is dependent on glucocorticoid levels; and 3) an increase in NHE-3 message, but not in NHE-1 or NHE-2 message, correlates with the stimulation of ileal brush border Na+/H+ exchange. It is likely that NHE-3 is an Na+/H+ exchanger that is involved in ileal Na+ absorption. PMID:8380155

Yun, C H; Gurubhagavatula, S; Levine, S A; Montgomery, J L; Brant, S R; Cohen, M E; Cragoe, E J; Pouyssegur, J; Tse, C M; Donowitz, M

1993-01-01

461

Osservazioni sulla morfo-biologia del Pnigalio mediterraneus Ferr. & del. ( Hym. eulophidae )  

Microsoft Academic Search

\\u000a Résumé  L'Auteur confirme les observations deSilvestri concernant la polyphagie de l'espècePnigalio mediterraneus\\u000a Ferr. etDel. Le parasite attaque en Italie aussi bienLithocolletis millierella\\u000a Stgr. etL. blancardella\\u000a F., queDacus oleae\\u000a Gml. Il se développe aux dépens de mineuses de feuilles au printemps et attaque de préférence leDacus en été et en automne. L'auteur découvre ensuite que lePnigalio en question peut être un parasite

G. Viggiani

1963-01-01

462

La guerra del fin del mundo: historia e invencion en una novela historica  

E-print Network

, sino mediante una amplia plasmacion del ser, mediante la presentaci6n de c6mo las ideas, los sentimientos y los modos de actuar nacen de cate terreno historico" (Lukacs, 54). Este concepto de la autenticidad y la fidelidad historicas supone que... vision no menos real, pese a no ser "documentable" en el sentido estricto. La novels historica ha sufrido ataques de parte de los historiadores con respecto a los errores y el desconocimiento de la epoca que los novelistas pretendian recrear, mientras...

Loeffler, Lisa Bowe

1984-01-01

463

Investigation of the thermonuclear 18Ne(?,p)21Na reaction rate via resonant elastic scattering of 21Na + p  

NASA Astrophysics Data System (ADS)

The 18Ne(?,p)21Na reaction is thought to be one of the key breakout reactions from the hot CNO cycles to the rp process in type I x-ray bursts. In this work, the resonant properties of the compound nucleus 22Mg have been investigated by measuring the resonant elastic scattering of 21Na + p. An 89-MeV 21Na radioactive beam delivered from the CNS Radioactive Ion Beam Separator bombarded an 8.8 mg/cm2 thick polyethylene (CH2)n target. The 21Na beam intensity was about 2×105 pps, with a purity of about 70% on target. The recoiled protons were measured at the center-of-mass scattering angles of ?c.m.?175.2?, 152.2?, and 150.5? by three sets of ?E-E telescopes, respectively. The excitation function was obtained with the thick-target method over energies Ex(22Mg)=5.5-9.2 MeV. In total, 23 states above the proton-threshold in 22Mg were observed, and their resonant parameters were determined via an R-matrix analysis of the excitation functions. We have made several new J? assignments and confirmed some tentative assignments made in previous work. The thermonuclear 18Ne(?,p)21Na rate has been recalculated based on our recommended spin-parity assignments. The astrophysical impact of our new rate has been investigated through one-zone postprocessing x-ray burst calculations. We find that the 18Ne(?,p)21Na rate significantly affects the peak nuclear energy generation rate, reaction fluxes, and onset temperature of this breakout reaction in these astrophysical phenomena.

Zhang, L. Y.; He, J. J.; Parikh, A.; Xu, S. W.; Yamaguchi, H.; Kahl, D.; Kubono, S.; Mohr, P.; Hu, J.; Ma, P.; Chen, S. Z.; Wakabayashi, Y.; Wang, H. W.; Tian, W. D.; Chen, R. F.; Guo, B.; Hashimoto, T.; Togano, Y.; Hayakawa, S.; Teranishi, T.; Iwasa, N.; Yamada, T.; Komatsubara, T.; Zhang, Y. H.; Zhou, X. H.

2014-01-01

464

Occlusion of ²²Na+ and ⁸⁶Rb+ in membrane-bound and soluble protomeric alpha beta-units of Na,K-ATPase  

Microsoft Academic Search

In this work, we examined occlusion of ²²Na+ and ⁸⁶Rb+ in membranous and detergent-solubilized Na,K-ATPase from outer renal medulla. Optimum conditions for occlusion of ²²Na+ were provided by formation of the phosphorylated complex from the beta,gamma-bidentate complex of chromium (III) with ATP (CrATP). Release of occluded cations occurred at equally slow rates in soluble and membrane-bound Na,K-ATPase. Values of ²²Na+

B. Vilsen; J. P. Andersen; J. Petersen; P. L. Jorgensen

1987-01-01

465

Futuras fuentes de crecimiento de la productividad del trigo en la region del Baj?o (Guanajuato, Mexico)  

Microsoft Academic Search

El objetivo de esta investigaci?n es determinar la perspectiva de la producci?n de trigo en la regi?n del Baj?o (Guanajuato, M?xico), como una zona estrat?gica para proveer la materia prima que requiere la industria molinera de la zona centro del pa?s. Se determin? el comportamiento de los componentes de la producci?n mediante el c?lculo de las tasas de crecimiento. Asimismo,

Pedro Aquino-Mercado

2003-01-01

466

Etch Induction Time in CR-39 Detectors Etched in Na2CO3 Mixed NaOH Solution  

NASA Astrophysics Data System (ADS)

Six different solutions of 6M NaOH, containing different amounts of Na2CO3 at 70°C were used for the revelation of latent damage trails in CR-39 plastic track detectors. These detectors were earlier exposed to fission fragments from 252Cf source for 30 min in vacuum and were then etched in the respective solutions for different etching time intervals of 5-20 min starting from 5min up to 160min. The etch induction time in each detector was obtained by extrapolating the intersection of resulting curves of track lengths and track diameters with the time axis.

N., Ali; Khan U., E.; K., Khan

2009-09-01

467

background Na+ conductance in pacemaking activity is unproven,  

E-print Network

background Na+ conductance in pacemaking activity is unproven, only the hasty would suggest that it is unlikely. Arrested pacemaker cells have membrane potentials of -35mY: some outward current must flow the membranes of arrested pacemaker cells whereas vagal stimulation does7. In beat- ing hearts vagal stimulation

Apkarian, A. Vania

468

Project ELaNa and NASA's CubeSat Initiative  

NASA Technical Reports Server (NTRS)

This slide presentation reviews the NASA program to use expendable lift vehicles (ELVs) to launch nanosatellites for the purpose of enhancing educational research. The Education Launch of Nanosatellite (ELaNa) project, run out of the Launch Services Program is requesting proposals for CubeSat type payload to provide information that will aid or verify NASA Projects designs while providing higher educational research

Skrobot, Garrett Lee

2010-01-01

469

O pleno emprego na perspectiva da modernização reflexiva  

Microsoft Academic Search

Resumo O pleno emprego foi o esteio para a segurança social na Primeira Modernidade. As políticas keynesianas implementadas a partir da crise de 1929 caminharam em direção à composição de um Estado- nacional social. O próprio sucesso do capitalismo industrial provoca mudanças. O desenvolvimento tecnológico, a crescente riqueza e a queda do muro de Berlim impulsionam a sociedade industrial para

Maria do Carmo; Cataldi Muterle

470

The putative mechanism of Na+ absorption in euryhaline  

E-print Network

The putative mechanism of Na+ absorption in euryhaline elasmobranchs exists in the gills December 2006 Abstract We recently cloned an NHE3 orthologue from the gills of the euryhaline Atlantic in the gills of the stenohaline marine spiny dogfish shark (Squalus acanthias). NHE3 immunoreactivity

Evans, David H.

471

Optimization of Automated Float Glass Lines Byungsoo Na, Shabbir Ahmed  

E-print Network

Optimization of Automated Float Glass Lines Byungsoo Na, Shabbir Ahmed , George Nemhauser and Joel flat glass products being manufactured on float glass lines. New technologies are allowing float glass our methods are currently being implemented at a major float glass manufacturer. Abstract In automated

Ahmed, Shabbir

472

Exploring Neutron-Rich Oxygen Isotopes with MoNA  

E-print Network

The Modular Neutron Array (MoNA) was used in conjunction with a large-gap dipole magnet (Sweeper) to measure neutron-unbound states in oxygen isotopes close to the neutron dripline. While no excited states were observed in 24O, a resonance at 45(2) keV above the neutron separation energy was observed in 23O.

Frank, N; Bazin, D; Brown, J; DeYoung, P A; Finck, J E; Gade, A; Hinnefeld, J; Howes, R; Lecouey, J -L; Luther, B; Peters, W A; Scheit, H; Schiller, A; Thoennessen, M

2007-01-01

473

Exploring Neutron-Rich Oxygen Isotopes with MoNA  

E-print Network

The Modular Neutron Array (MoNA) was used in conjunction with a large-gap dipole magnet (Sweeper) to measure neutron-unbound states in oxygen isotopes close to the neutron dripline. While no excited states were observed in 24O, a resonance at 45(2) keV above the neutron separation energy was observed in 23O.

N. Frank; T. Baumann; D. Bazin; J. Brown; P. A. DeYoung; J. E. Finck; A. Gade; J. Hinnefeld; R. Howes; J. -L. Lecouey; B. Luther; W. A. Peters; H. Scheit; A. Schiller; M. Thoennessen

2007-08-20

474

Exploring Neutron-Rich Oxygen Isotopes with MoNA  

SciTech Connect

The Modular Neutron Array (MoNA) was used in conjunction with a large-gap dipole magnet (Sweeper) to measure neutron-unbound states in oxygen isotopes close to the neutron dripline. While no excited states were observed in {sup 24}O, a resonance at 45(2) keV above the neutron separation energy was observed in {sup 23}O.

Frank, N.; Gade, A.; Peters, W. A.; Thoennessen, M. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Baumann, T.; Bazin, D.; Lecouey, J.-L.; Scheit, H.; Schiller, A. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824 (United States); Brown, J. [Department of Physics, Wabash College, Crawfordsville, IN 47933 (United States); DeYoung, P. A. [Department of Physics, Hope College, Holland, MI 49423 (United States); Finck, J. E. [Department of Physics, Central Michigan University, Mt. Pleasant, MI 48859 (United States); Hinnefeld, J. [Department of Physics and Astronomy, Indiana University at South Bend, South Bend, IN 46634 (United States); Howes, R. [Department of Physics, Marquette University, Milwaukee, WI 53201 (United States); Luther, B. [Department of Physics, Concordia College, Moorhead, MN 56562 (United States)

2007-11-30

475

Regulation of Intracellular Cholesterol Distribution by Na/K-ATPase*  

E-print Network

Regulation of Intracellular Cholesterol Distribution by Na/K-ATPase* Received for publication/K-ATPase 1 subunit produces a parallel decrease in both caveolin-1 and cholesterol in light fractions of LLC redistribution of cholesterol from the plasma membrane to intracellular compartments in the knockdown cells

Brand, Paul H.

476

Multiple carbohydrate moieties on the Na+/H+ exchanger.  

PubMed Central

Affinity-purified antibodies against the C-terminal region of the Na+/H+ exchanger (NHE-1) were used to analyse the carbohydrate moiety of the protein. The Na+/H+ exchanger in human placental brush-border membranes has an apparent molecular mass of 105 kDa. Incubation of intact or detergent-solubilized membranes with glycopeptidase F removed the carbohydrate moiety and increased the apparent mobility of the exchanger. Digestion with endoglycosidase-F caused a similar change in mobility, but endoglycosidase-H had no effect, suggesting that the placental Na+/H+ exchanger is a glycoprotein of the biantennary complex type. Removal of the carbohydrate moiety with glycopeptidase F had no effect on the ability of the protein to promote the exchange of Na+ for H+, and had no detectable effect on the sensitivity of the exchanger to trypsin. Limited digestion with glycopeptidase F and neuraminidase indicated the presence of two intermediate forms between the fully glycosylated and the deglycosylated protein. This suggests the presence of at least two, and possibly three, N-linked carbohydrate moieties. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:8382044

Haworth, R S; Fröhlich, O; Fliegel, L

1993-01-01

477

Altered erythrocyte Na-K pump in anorectic patients  

SciTech Connect

The status of the erythrocyte sodium pump was evaluated in a group of patients suffering from anorexia nervosa and a group of healthy female control subjects. Anorectic patients showed significantly higher mean values of digoxin-binding sites/cell (ie, the number of Na-K-ATPase units) with respect to control subjects while no differences were found in the specific /sup 86/Rb uptake (which reflects the Na-K-ATPase activity) between the two groups. A significant correlation was found between relative weight and the number of Na-K-ATPase pump units (r = -0.66; P less than 0.0001). Anorectic patients showed lower serum T3 concentrations (71.3 +/- 53 ng/dL) with respect to control subjects (100.8 +/- 4.7 ng/dL; P less than 0.0005) and a significant negative correlation between T3 levels and the number of pump units (r = -0.52; P less than 0.003) was found. This study therefore shows that the erythrocyte Na-K pump may be altered in several anorectic patients. The authors suggest that this feature could be interrelated with the degree of underweight and/or malnutrition.

Pasquali, R.; Strocchi, E.; Malini, P.; Casimirri, F.; Ambrosioni, E.; Melchionda, N.; Labo, G.

1985-07-01

478

Hydroxyl groups in zeolites CaNaA  

NASA Astrophysics Data System (ADS)

OH groups on shallow-bed-treated zeolites CaNaA were studied using diffuse reflectance infrared spectroscopy in the near-infrared region. For activation temperatures in the range 160-280°C bridging OH groups were found. The bulk of OH groups, however, are AlOH on extra-framework aluminium.

Mix, H.; Pfeifer, H.; Staudte, B.

1988-05-01

479

O, Na, Ba and Eu abundance patterns in open clusters  

NASA Astrophysics Data System (ADS)

Open clusters are historically regarded as single-aged stellar populations representative of star formation within the Galactic disc. Recent literature has questioned this view, based on discrepant Na abundances relative to the field, and concerns about the longevity of bound clusters contributing to a selection bias: perhaps long-lived open clusters are chemically different to the star formation events that contributed to the Galactic disc. We explore a large sample of high-resolution Na, O, Ba and Eu abundances from the literature, homogenized as much as reasonable including accounting for non-local thermodynamic equilibrium (NLTE) effects, variations in analysis and choice of spectral lines. Compared to a template globular cluster and representative field stars, we find no significant abundance trends, confirming that the process producing the Na-O anticorrelation in globular clusters is not present in open clusters. Furthermore, previously reported Na enhancement of open clusters is found to be an artefact of NLTE effects, with the open clusters matching a subset of chemically tagged field stars.

MacLean, B. T.; De Silva, G. M.; Lattanzio, J.

2015-02-01

480

Results from NA60 experiment at the CERN SPS  

SciTech Connect

The NA60 experiment studies open charm and prompt dimuon production in proton-nucleus and nucleus-nucleus collisions at the CERN SPS. During 2003 the experiment collected data in Indium-Indium collisions at 158 GeV per nucleon. In this paper the first results on low mass dimuons, intermediate mass dimuons and J/{psi} suppression are presented.

Usai, G.; Cicalo, C.; De Falco, A.; Floris, M.; Masoni, A.; Puddu, G.; Serci, S. [Univ. di Cagliari, Cagliari (Italy); INFN, Cagliari (Italy); Arnaldi, R.; Colla, A.; Cortese, P.; Ferretti, A.; Oppedisano, C. [Univ. di Torino (Italy) and INFN (Italy); Averbeck, R.; Drees, A. [SUNY Stony Brook, New York (United States); Banicz, K. [CERN, Geneva (Switzerland); Univ. Heidelberg, Heidelberg (Germany); Castor, J.; Devaux, A.; Force, P.; Manso, F. [LPC, Univ. Blaise Pascal, Clermont-Ferrand (France); CNRS-IN2P3, Clermont-Ferrand (France); Chaurand, B. [LLR, Ecole Polytechnique, Palaiseau (France); CNRS-IN2P3, Palaiseau (France)] (and others)

2006-07-11

481

Thyroid Na /I Symporter MECHANISM, STOICHIOMETRY, AND SPECIFICITY*  

E-print Network

. It is now firmly established that active accumulation of io- dide (I ) by the thyroid gland epithelium membrane of the thyroid gland follicular cells. Io- dide transport into the thyroid gland has attractedThyroid Na /I Symporter MECHANISM, STOICHIOMETRY, AND SPECIFICITY* (Received for publication, May

Eskandari, Sepehr

482

Tecnologia de Agentes na Convergncia das Telecomunicaes com a Computao  

E-print Network

Tecnologia de Agentes na Convergência das Telecomunicações com a Computação Joaquim Croca Eng desafios considera-se o paradigma e a tecnologia dos agentes de software como uma aproximação adequada, com de recentes desenvolvimentos de tecnologias como o TINA-C, CORBA ou Web Services. Alguns

da Silva, Alberto Rodrigues

483

A reinvenção da sexualidade masculina na paraplegia adquirida  

Microsoft Academic Search

RESUMO Neste trabalho a sexualidade masculina é discutida a partir da condição de um homem com lesão medular. Seu objetivo foi investigar o impacto da paraplegia adquirida na sexualidade masculina. Metodologicamente adotou-se uma aborda- gem qualitativa e coletou-se a história de vida por meio de entrevistas. As princi- pais conclusões apontam para um deslocamento das representações da masculi- nidade associadas

Luiz Carlos Avelino da Silva; Paulo Albertini

2007-01-01

484

Elucidation of the Na+, K+-ATPase digitalis binding site.  

PubMed

Despite controversy over their use and the potential for toxic side effects, cardiac glycosides have remained an important clinical component for the treatment for congestive heart failure (CHF) and supraventricular arrhythmias since the effects of Digitalis purpurea were first described in 1785. While there is a wealth of information available with regard to the effects of these drugs on their pharmacological receptor, the Na(+), K(+)-ATPase, the exact molecular mechanism of digitalis binding and inhibition of the enzyme has remained elusive. In particular, the absence of structural knowledge about Na(+), K(+)-ATPase has thwarted the development of improved therapeutic agents with larger therapeutic indices via rational drug design approaches. Here, we propose a binding mode for digoxin and several analogues to the Na(+), K(+)-ATPase. A 3D-structural model of the extracellular loop regions of the catalytic alpha1-subunit of the digitalis-sensitive sheep Na(+), K(+)-ATPase was constructed from the crystal structure of an E(1)Ca(2+) conformation of the SERCA1a and a consensus orientation for digitalis binding was inferred from the in silico docking of a series of steroid-based cardiotonic compounds. Analyses of species-specific enzyme affinities for ouabain were also used to validate the model and, for the first time, propose a detailed model of the digitalis binding site. PMID:15886034

Keenan, Susan M; DeLisle, Robert K; Welsh, William J; Paula, Stefan; Ball, William J

2005-06-01

485

National Aeronautics and Space Administration NaNotechNology Roadmap  

E-print Network

National Aeronautics and Space Administration · NaNotechNology Roadmap Technology Area 10 Michael A: Nanotechnology. NASA developed this DRAFT Space Technology Roadmap for use by the National Research Council (NRC Nanotechnology involves the manipulation of matter at the atomic level, where convention- al physics breaks down

Waliser, Duane E.

486

Študent naj bo na ameriškem kolidžu  

E-print Network

zabavo in da niso neusmiljeno tekmovalni (kar je precej redek pojav na najzahtevnejših 172 ~olah). Ker je bil to ?etrtek zve?er. jih je bila ve?ina zelo zaposlenih z nalogami in projekti - povedali so mu, da se zabave dogajajo ?ez vikend - a nekaj jih...

Pirnat-Greenberg, Marta

2007-01-01

487

Synthesis of Na-zeolites from fly ash  

Microsoft Academic Search

The present study focuses on the synthesis of zeolites after fly ash activation, the major objectives being: (a) to study the activation processes; (b) to elucidate the activation conditions for maximum synthesis efficiency; (c) to optimize the conditions for the monomineral synthesis; and (d) to test synthesis efficiencies for different fly ash types. Fly ash was activated by NaOH and

Xavier Querol; Felicià Plana; Andrés Alastuey; Angel López-Soler

1997-01-01

488

Effects of Na2MoO4 and Na2WO4 on molybdenum and tungsten electrodes for the alkali metal thermoelectric converter (AMTEC)  

NASA Technical Reports Server (NTRS)

The effects of adding Na2MoO4 and Na2WO4 to porous Mo and W electrodes, respectively, on the performance and impedance characteristics of the electrodes in an alkali metal thermoelectric converter (AMTEC) were investigated. It was found that corrosion of the porous electrode by Na2MoO4 or Na2WO4 to form Na2MO3O6 and WO2, respectively, and recrystallization of the Mo or W as the salt evaporates, result in major morphological changes including a loss of columnar structure and a significant increase in porosity. This effect is more pronounced in Na2MoO4/Mo electrodes, due to the lower stability of Na2MoO4.

Williams, R. M.; Wheeler, B. L.; Jeffries-Nakamura, B.; Loveland, M. E.; Bankston, C. P.

1988-01-01

489

La judicializacin del caso de la pldora del da despus en Chile: las tensiones sobre el rol de la mujer y la cuestin tcnica1  

E-print Network

que serán supeditadas al contexto social en cual la política se inscribe. Introducción El Chile de la1 La judicialización del caso de la píldora del día después en Chile: las tensiones sobre el rol de en torno a la introducción de la píldora del día después en Chile. Esta discusión se posicionó en la

Paris-Sud XI, Université de

490

Regulation of intracellular Na+ in health and disease: pathophysiological mechanisms and implications for treatment  

PubMed Central

Transmembrane sodium (Na+) fluxes and intracellular sodium homeostasis are central players in the physiology of the cardiac myocyte, since they are crucial for both cell excitability and for the regulation of the intracellular calcium concentration. Furthermore, Na+ fluxes across the membrane of mitochondria affect the concentration of protons and calcium in the matrix, regulating mitochondrial function. In this review we first analyze the main molecular determinants of sodium fluxes across the sarcolemma and the mitochondrial membrane and describe their role in the physiology of the healthy myocyte. In particular we focus on the interplay between intracellular Ca2+ and Na+. A large part of the review is dedicated to discuss the changes of Na+ fluxes and intracellular Na+ concentration([Na+]i) occurring in cardiac disease; we specifically focus on heart failure and hypertrophic cardiomyopathy, where increased intracellular [Na+]i is an established determinant of myocardial dysfunction. We review experimental evidence attributing the increase of [Na+]i to either decreased Na+ efflux (e.g. via the Na+/K+ pump) or increased Na+ influx into the myocyte (e.g. via Na+ channels). In particular, we focus on the role of the “late sodium current” (INaL), a sustained component of the fast Na+ current of cardiac myocytes, which is abnormally enhanced in cardiac diseases and contributes to both electrical and contractile dysfunction. We analyze the pathophysiological role of INaL enhancement in heart failure and hypertrophic cardiomyopathy and the consequences of its pharmacological modulation, highlighting the clinical implications. The central role of Na+ fluxes and intracellular Na+ physiology and pathophysiology of cardiac myocytes has been highlighted by a large number of recent works. The possibility of modulating Na+ inward fluxes and [Na+]i with specific INaL inhibitors, such as ranolazine, has made Na+a novel suitable target for cardiac therapy, potentially capable of addressing arrhythmogenesis and diastolic dysfunction in severe conditions such as heart failure and hypertrophic cardiomyopathy. PMID:24689024

Coppini, Raffaele; Ferrantini, Cecilia; Mazzoni, Luca; Sartiani, Laura; Olivotto, Iacopo; Poggesi, Corrado; Cerbai, Elisabetta; Mugelli, Alessandro

2013-01-01

491

Light-driven Na(+) pump from Gillisia limnaea: a high-affinity Na(+) binding site is formed transiently in the photocycle.  

PubMed

A group of microbial retinal proteins most closely related to the proton pump xanthorhodopsin has a novel sequence motif and a novel function. Instead of, or in addition to, proton transport, they perform light-driven sodium ion transport, as reported for one representative of this group (KR2) from Krokinobacter. In this paper, we examine a similar protein, GLR from Gillisia limnaea, expressed in Escherichia coli, which shares some properties with KR2 but transports only Na(+). The absorption spectrum of GLR is insensitive to Na(+) at concentrations of ?3 M. However, very low concentrations of Na(+) cause profound differences in the decay and rise time of photocycle intermediates, consistent with a switch from a "Na(+)-independent" to a "Na(+)-dependent" photocycle (or photocycle branch) at ?60 ?M Na(+). The rates of photocycle steps in the latter, but not the former, are linearly dependent on Na(+) concentration. This suggests that a high-affinity Na(+) binding site is created transiently after photoexcitation, and entry of Na(+) from the bulk to this site redirects the course of events in the remainder of the cycle. A greater concentration of Na(+) is needed for switching the reaction path at lower pH. The data suggest therefore competition between H(+) and Na(+) to determine the two alternative pathways. The idea that a Na(+) binding site can be created at the Schiff base counterion is supported by the finding that upon perturbation of this region in the D251E mutant, Na(+) binds without photoexcitation. Binding of Na(+) to the mutant shifts the chromophore maximum to the red like that of H(+), which occurs in the photocycle of the wild type. PMID:25375769

Balashov, Sergei P; Imasheva, Eleonora S; Dioumaev, Andrei K; Wang, Jennifer M; Jung, Kwang-Hwan; Lanyi, Janos K

2014-12-01

492

Na+-independent phosphate transport in Caco2BBE cells.  

PubMed

Pi transport in epithelia has both Na(+)-dependent and Na(+)-independent components, but so far only Na(+)-dependent transporters have been characterized in detail and molecularly identified. Consequently, in the present study, we initiated the characterization and analysis of intestinal Na(+)-independent Pi transport using an in vitro model, Caco2BBE cells. Only Na(+)-independent Pi uptake was observed in these cells, and Pi uptake was dramatically increased when cells were incubated in high-Pi DMEM (4 mM) from 1 day to several days. No response to low-Pi medium was observed. The increased Pi transport was mainly caused by Vmax changes, and it was prevented by actinomycin D and cycloheximide. Pi transport in cells grown in 1 mM Pi (basal DMEM) decreased at pH > 7.5, and it was inhibited with proton ionophores. Pi transport in cells incubated with 4 mM Pi increased with alkaline pH, suggesting a preference for divalent phosphate. Pi uptake in cells in 1 mM Pi was completely inhibited only by Pi and partially inhibited by phosphonoformate, oxalate, DIDS, SITS, SO4 (2-), HCO3 (-), and arsenate. This inhibition pattern suggests that more than one Pi transporter is active in cells maintained with 1 mM Pi. Phosphate transport from cells maintained at 4 mM Pi was only partially inhibited by phosphonoformate, oxalate, and arsenate. Attempts to identify the responsible transporters showed that multifunctional anion exchangers of the Slc26 family as well as members of Slc17, Slc20, and Slc37 and the Pi exporter xenotropic and polytropic retrovirus receptor 1 are not involved. PMID:25298422

Candeal, Eduardo; Caldas, Yupanqui A; Guillén, Natalia; Levi, Moshe; Sorribas, Víctor

2014-12-15

493

Characterization of Na+K+-ATPase in bovine sperm.  

PubMed

Existing as a ubiquitous transmembrane protein, Na(+)K(+)-ATPase affects sperm fertility and capacitation through ion transport and a recently identified signaling function. Functional Na(+)K(+)-ATPase is a dimer of ? and ? subunits, each with isoforms (four and three, respectively). Since specific isoform pairings and locations may influence or indicate function, the objective of this study was to identify and localize subunits of Na(+)K(+)-ATPase in fresh bull sperm by immunoblotting and immunocytochemistry using antibodies against ?1 and 3, and all ? isoforms. Relative quantity of Na(+)K(+)-ATPase in head plasma membranes (HPM's) from sperm of different bulls was determined by densitometry of immunoblot bands, and compared to bovine kidney. Sperm and kidney specifically bound all antibodies at kDa equivalent to commercial controls, and to additional lower kDa bands in HPM. Immunofluorescence of intact sperm confirmed that all isoforms were present in the head region of sperm and that ?3 was also uniformly distributed post-equatorially. Permeabilization exposing internal membranes typically resulted in an increase in fluorescence, indicating that some antibody binding sites were present on the inner surface of the HPM or the acrosomal membrane. Deglycosylation of ?1 reduced the kDa of bands in sperm, rat brain and kidney, with the kDa of the deglycosylated bands differing among tissues. Two-dimensional blots of ?1 revealed three distinct spots. Based on the unique quantity, location and structure Na(+)K(+)-ATPase subunits in sperm, we inferred that this protein has unique functions in sperm. PMID:22284223

Hickey, Katie D; Buhr, Mary M

2012-04-15

494

Semi-volatiles at Mercury: Sodium (Na) and potassium (K)  

NASA Technical Reports Server (NTRS)

Several lines of evidence now suggest that Mercury is a planet rich in moderately-volatile elements such as Na and K. Recent mid-infrared spectral observations of Mercury's equatorial and mid-latitude region near 120 degrees mercurian longitude indicate the presence of plagioclase feldspar. Spectra of Mercury's surface exhibit spectral activity similar to labradorite (plagioclase feldspar with NaAlSi3O8: 30-50 percent) and bytownite (NaAlSi3O8: 10-30 percent). These surface studies were stimulated by the relatively large abundance of Na and K observed in Mercury's atmosphere. An enhanced column of K is observed at the longitudes of Caloris Basin and of the antipodal terrain. Extreme heating at these 'hot' longitudes and severe fracturing suffered from the large impact event could lead to enhanced outgassing from surface or subsurface materials. Alternatively, sputtering from a surface enriched in K could be the source of the observed enhancement. Recent microwave measurements of Mercury also give indirect evidence of a mercurian regolith less FeO-rich than the Moon. An anomalously high index of refraction derived from the whole-disk integrated phase curve of Danjon may also be indicative of surface sulfides contributing to a regolith that is moderately volatile-rich. The recent exciting observations of radar-bright spots at high latitudes also indicate that a substance of high volume scattering, like ice, is present in shadowed regions. Other radar-bright spots have been seen at locations of Na enhancements on the atmosphere. All combined, these pieces of evidence point to a planet that is not severely depleted in volatiles or semi-volatiles.

Sprague, A.

1994-01-01

495

Aldosterone augments Na+-induced reduction of cardiac norepinephrine reuptake.  

PubMed

Impairment of the cardiac norepinephrine (NE) reuptake by the neuronal NE transporter contributes to enhanced cardiac NE net release in congestive heart failure. Elevated plasma levels of aldosterone (AL) promote sympathetic overstimulation in failing hearts by unclear mechanisms. Our aim was to evaluate if elevated AL and/or alterations in Na(+) intake regulate cardiac NE reuptake. To test the effects of AL and Na(+) on cardiac NE reuptake, Wistar rats were fed a normal-salt (NS) diet (0.2% NaCl), a low-salt (LS) diet (0.015% NaCl), or a high-salt (HS) diet (8% NaCl). Another group of animals received AL infusion alone (0.75 ?g/h) or AL infusion plus HS diet. Specific cardiac [(3)H]NE uptake via the NE transporter in a Langendorff preparation and AL plasma levels were measured at different time points between 5 and 42 days of treatment. To compare these findings from healthy animals with a disease model, Dahl salt-sensitive rats were investigated as a model of congestive heart failure with endogenously elevated AL. In summary, neither exogenous nor endogenous elevations of AL alone were sufficient to reduce cardiac NE reuptake. Only the HS diet induced a reduction of NE reuptake by 26%; additional infusion of AL augmented this effect to a further reduction of NE reuptake by 36%. In concordance, Dahl salt-sensitive rats treated with a HS diet displayed elevated AL and a marked reduction of NE reuptake. We conclude that exogenous or endogenous AL elevations alone do not reduce cardiac NE reuptake, but AL serves as an additional factor that negatively regulates cardiac NE reuptake in concert with HS intake. PMID:25128164

Kreusser, Michael M; Lehmann, Lorenz H; Riffel, Johannes H; Haass, Markus; Maser-Gluth, Christiane; Backs, Johannes; Katus, Hugo A; Buss, Sebastian J

2014-10-15

496

Na double-edge magneto-optic filter for Na lidar profiling of wind and temperature in the  

E-print Network

within a longitudinal magnetic field B between two polarizers. The difference is a quarter-wave plate and then followed by polarization analysis with a quarter-wave plate and a polarized beam splitter. The static. © 2009 Optical Society of America OCIS codes: 280.3640, 300.6210, 010.3640. Resonance fluorescence Na

Chu, Xinzhao

497

Componentes naturales y de uso del suelo vulnerables a las variaciones del nivel del mar en la costa atlántica de México  

Microsoft Academic Search

Palabras clave Regionalizaci6n de costas, fislografia, vulnerabilidad costera, uso del suelo Absúact Geomorphological alaradenstia of the mastal iongitudinal prn* and the arrangwent of the physiographical stmcture allowed the rmnition of two zonas: a) the intertidai zone -a basic sntne for dired imoaci of sea leve1 dame: and b) an adjacent peritidál (supralittoral) hnge &n area of cushioning or of polential

Mano Arturo; Ortiz Pérez; Ana Patricia; Méndez Linares

498

LOS NIVELES EMPÍRICO Y TEÓRICO DEL CONOCIMIENTO Y LA UTILIZACIÓN DEL MÉTODO HISTORICO LÓGICO EN LA FUNDAMENTACIÓN DEL APORTE TEORICO DE UNA TESIS DOCTORAL  

Microsoft Academic Search

En su función de tribunal y oponente a variadas tesis doctorales desarrolladas en los últimos tiempos se ha constatado, por los autores de este trabajo, algunos problemas en la aplicación de los métodos del pensamiento científico que dificultan a los aspirantes definir y defender los aportes fundamentales de sus investigaciones. A tono con estas situaciones a aparecido para los jóvenes